A Bandwidth-Efficient Architecture for Media Processing
12代英特尔核心桌面处理器产品介绍说明书
The 12th Gen Intel® Core™ desktop processor redefines x86 architecture performance. Introducing our new performance hybrid architecture, combining Performance-cores with Efficient-cores to elevate gaming, productivity, and creation. These breakthrough processors intelligently optimize workloads and pave the way for future leaps in processor design. Enjoy the full range of the latest platform innovations like industry first PCIe 5.0 readiness and DDR5 memory. With Intel® UHD graphics immerse yourself in a visually stunning experience with up to 8K HDR support and the ability to view 4 simultaneous 4K displays. 12th Gen Intel® Core™ desktop processors bring all the features you need to game, work, and create like never before.12thGen Intel® Core™ Desktop ProcessorsWhether you’re delving into the latest gaming titles or focusing on advanced professional applications, 12th Gen Intel® Core™ Desktop processors enable you to immerse without interruptions. Intel® UHD Graphics driven by X e Architecture invite you to take a deep-dive into vivid new experiences with enhanced visual support for up to 8K HDR video in billions of colors and up to 4 simultaneous 4K displays. 12th Gen Intel® Core™ desktop processors are capable of canceling out interruptions with enhanced Gaussian & Neural Accelerator 3.0 (GNA) for more efficient noise suppression and back-ground blurring on video. For elite gaming, world-class productivity, free flowing creation, and more, 12th Gen Intel® Core™ desktop processors enable deep immersion and focus.Immersive ExperiencesAccelerating Platform InnovationTap into the latest platform technologies that drive incredible gaming, workflow, and creation. Our 12th Gen Intel® Core™ desktop processors offer up to 20 lanes (16 PCIe 5.0 and 4 PCIe 4.0) to drive optimal discrete graphics and storage performance by enabling higher bandwidth connection points. DDR5 brings fast speeds up to 4800 MT/s, this allows for increased memory bandwidth speeds compared to previous genera-tions that use DDR4 3200 MT/s memory.2 Fine tune both compute power and performance with unlocked 12th Gen Intel® Core™ desktop processors that have overclocking capabili-ties and Advanced Tuning support via Intel® Extreme Tuning Utility (XTU).3 With these and other platform enhancements you’ll be able to work, game, and create with impressive control and confidence.FEATURE BENEFITPerformance Hybrid Architecture Performance hybrid architecture, combining Performance-cores (P-cores)and Efficient-cores (E-Cores) to deliver balanced single-thread and multi-threadedreal-world performance.Intel® Thread Director1Optimizes workloads by helping the OS scheduler intelligently distribute workloadsto the optimal cores.PCIe 5.0 up to 16 Lanes Offers readiness for up to 32 GT/s for fast access to peripheral devices and networkingwith up to 16 PCI Express 5.0 lanes.PCIe 4.0 up to 4 Lanes Offers up to 16 GT/s for fast access to peripheral devices and networking withup to 4 PCI Express 4.0 lanes.Up to DDR5 4800 MT/s2This industry first memory technology supports fast frequencies and high bandwidthand throughput leading to enhanced workflow and productivity.Up to DDR4 3200 MT/s2Supports faster frequencies and higher bandwidth and throughput leadingto enhanced workflow and productivity.L3 and L2 Cache Increased shared Intel® Smart Cache (L3) and L2 cache sizes deliver large memorycapacity and reduced latency for fast game loading and smooth frame rates.Intel® Deep Learning Boost Accelerates AI inference to improve performance for deep learning workloads.Gaussian & Neural Accelerator 3.0 (GNA 3.0)IProcesses AI speech and audio applications such as neural noise cancellation while simultaneously freeing up CPU resources for overall system performance and responsiveness.Intel® Turbo Boost Max Technology 3.0Identifies the processor’s fastest cores and directs critical workloads to them.Intel® UHD Graphics driven by X e Architecture Rich media and intelligent graphics capabilities enable amplified visual complexity, enhanced 3D performance, and faster image processing.Overclocking Features and Capabilities When paired with the Intel® Z690 chipset, processor P-cores, E-cores, graphics, and memory can be set to run at frequencies above the processor specification resulting in higher performance.Intel® Core™i9-12900K & i9-12900KF4Intel® Core™i7-12700K &i7-12700KF4Intel® Core™i5-12600K &i5-12600KF4Max Turbo Frequency [GHz]Up to 5.2Up to 5.0Up to 4.9 Intel® Turbo Boost Max Technology3.0 Frequency [GHz]Up to 5.2Up to 5.0n/a Single P-core Turbo Frequency [GHz]Up to 5.1Up to 4.9Up to 4.9 Single E-core Turbo Frequency [GHz]Up to 3.9Up to 3.8Up to 3.6P-core Base Frequency [GHz] 3.2 3.6 3.7E-core Base Frequency [GHz] 2.4 2.7 2.8 Processor Cores (P-cores + E-cores)16 (8P + 8E)12 (8P + 4E)10 (6P + 4E) Intel® Hyper-Threading Technology5Yes Yes YesTotal Processor Threads242016Intel® Thread Director1Yes Yes YesIntel® Smart Cache (L3) Size [MB]302520Total L2 Cache Size [MB]14129.5Max Memory Speed [MT/s] Up to DDR5 4800Up to DDR4 3200Up to DDR5 4800Up to DDR4 3200Up to DDR5 4800Up to DDR4 3200Number of Memory Channels222CPU PCIe 5.0 Lanes161616CPU PCIe 4.0 Lanes444Enhanced Intel® UHD Graphics drivenby X e ArchitectureIntel® UHD Graphics 770Intel® UHD Graphics 770Intel® UHD Graphics 770 Graphics Dynamic Frequency [MHz]Up to 1550Up to 1500Up to 1450Processor P-core/E-core/Graphics/Memory Overclocking3Yes Yes YesIntel® Quick Sync Video Yes Yes YesIntel® Deep Learning Boost (Intel® DL Boost)Yes Yes YesIntel® Advanced Vector Extensions 2 (Intel® AVX2)Yes Yes YesIntel® Gaussian and Neural Accelerator (GNA) 3.0Yes Yes YesIntel® Virtualization Technology (Intel® VT-x / VT-d)Yes Yes YesMode-based Execution Control (MBEC)Yes Yes YesIntel® Threat Detection Technology (Intel® TDT)Yes Yes YesIntel® Control-Flow Enforcement Technology(Intel® CET)Yes Yes YesIntel® Advanced Encryption Standard NewInstructions (Intel® AES-NI)Yes Yes YesIntel® BIOS Guard Yes Yes YesIntel® Boot Guard Yes Yes YesIntel® OS Guard Yes Yes YesIntel® Advanced Programmable Interrupt ControllerVirtualization (Intel® APIC-v)Yes Yes YesIntel® Secure Key Yes Yes YesIntel® Platform Trust Technology (Intel® PTT)Yes Yes YesProduct Brief ©Intel Corporation. Intel, the Intel logo, and other Intel marks are trademarks of Intel Corporation or its subsidiaries. Other names and brands may be claimed as the property of others.Notices & Disclaimers1Intel® Thread Director is designed into 12th Gen Intel® Core™ processors and helps supportingoperating systems to more intelligently channel workloads to the right core. No user action required. See for details.2Based on memory bandwidth results using Intel® Memory Latency Checker Tool v3.9a System A: Core i9-12900K on Asus Z690 TUF DDR4 Motherboard. 2x16GB G.Skill TridentZ 3200Mhz CL14 RAM System B: Core i9-12900K on Asus Z690 Prime-P DDR5 Motherboard. 2x16GB SK.Hynix 4400Mhz CL40 RAM.3Altering clock frequency or voltage may damage or reduce the useful life of the processor and other system components, and may reduce system stability and performance. Product warranties may not apply if the processor is operated beyond its specifications. Check with the manufacturers of system and components for additional details.4Processor names with an ‘F’ suffix do not have processor graphics and require a discrete graphics solution. Without processor graphics the processor display output ports will not function. 5Intel® Hyper-Threading Technology is only available on P-cores.Performance varies by use, configuration and other factors. Learn more at /PerformanceIndex .Performance results are based on testing as of dates shown in configurations and may not reflect all publicly available u pdates. See backup for configuration details. No product or component can be abso-lutely secure.Your costs and results may vary.Intel technologies may require enabled hardware, software or service activation.Altering clock frequency or voltage may void any product warranties and reduce stability, security, performance, and life of the processor and other components. Check with system and component manufacturers for details.For use only by product developers, software developers, and system integrators. For evaluation only; not FCC approved for resaleThis device has not been authorized as required by the rules of the Federal Communications Commission. This device is not, and may not be, offered for sale or lease, or sold or leased, until authorization is obtained.Statements in this document that refer to future plans or expectations are forward-looking statements. These statements are based on current expectations and involve many risks and uncertainties that could cause actual results to differ materially from those expressed or implied in such statements. For more information on the factors that could cause actual results to differ materially, see our most recent earnings release and SEC filings at .12th Gen Intel® Core™ Desktop Processors。
华为云引擎系列交换机技术介绍说明书
CloudEngine Is the Foundation of the Intent-driven NetworkHuawei CloudEngine Series Switches Technical PresentationContentsClick to add Title 1Click to add Title 2Click to add Title 3CloudEngine Switch OverviewCloudEngine Switch HighlightsCloudEngine Switch Market ProgressSwitches Are the Cornerstone for Transforming Data Centers from Service Centers to Value CentersCloud computingBig DataDistributed storageMetcalfe's Law: The effect of a telecommunications network is proportional to the square of the number of connected users of the system.-Robert Metcalfe who invented Ethernet, founder of 3Com In the future, even if all hardware network devices will disappear, data center switches used as the buses connecting to servers, will always exist. The Ethernet helps release the value of data.AISDN NFVIntent-driven networkUltra-broadbandInfrastructureSimplifiedOpenController and management tool layerControllerAnalyzerSecurityCharacteristics of the Future of DC Switches: Ultra-broadband, Simplified, Intelligent, Secure, and OpenIntelligentSecureManagementControlAnalysisOpenConvergenceEcosystemSpine LeafGatewayBandwidth -> LatencyLayer 2 and Layer 3 -> SecurityManual driving -> Automated drivingWeb page -> Service integrationCloudEngine Series Data Center Switches Portfolio(1)Core SwitchesAccess SwitchesCloudEngine 6881-48S6CQ (New)CloudEngine 6863-48S6CQ (New)CloudEngine 16800 (New)CloudEngine 16816CloudEngine 16808CloudEngine 1680410GE ToR switch25GE ToR switchCloudEngine Series Data Center Switches Portfolio(2)Core SwitchesAccess Switches10GE ToR switchCE6851-48S6Q-HICE6810-48S4Q-LICE6810-32T16S4Q-LIGE ToR switchCE5855-48T4S2Q-EICE5855-24T4S2Q-EIVirtual SwitchesCE1800VCE6855/CE6856-48S6Q-HICE6855/CE6856-48T6Q-HI10GE large-buffer ToR switchCE6870-48S6CQ-EIToR switch with flexible cardsCE8861-4C-EI40GE switchCE7855-32Q-EICE6865-48S8CQ-EI25GE ToR switch100GE switchCE8850-64CQ-EICE12816CE12812CE12808CE12808S CE12804SCE12804CE12800CE12800SCE6870-48T6CQ-EICE6875-48S4CQ-EICE8850-32CQ-EICE6860-48S8CQ-EICE6857-48S6CQ-EICE8860-4C-EICE5880-48T6Q-EICE6880-24S4Q2CQ-EIOrthogonal architectureStrict front-to-back airflow designNon-blocking switchingCounter-rotating fansLine cardNo cabling of the backplaneIncreased bandwidth of the entire systemCE12800Patent No.: CN201110339954.1Independent front-to-back airflowEven heat dissipation, suitable for data centersCell switching and VoQTraffic balancing, improving bandwidth utilizationCounter-rotating and turbo fansHighly efficient heat dissipationLeading energy-conserving designHigh-Quality CloudEngine: High-Quality Architecture Creates a Green and Stable Network•Industry-leading architecture design and high quality:orthogonal SFU design,Clos architecture,cell switching,and Virtual Output Queue (VOQ)mechanism 1/31/31/31/31/31/31/31/31/31/31/31/31/31/31/31/31/31/3ContentsClick to add Title 1Click to add TitleCloudEngine Switch Overview3CloudEngine Switch Market Progress▪Ultra-broadband Cloud Engine ▪Simplified Cloud Engine ▪Intelligent Cloud Engine▪Secure Cloud Engine ▪Open Cloud Engine2CloudEngine Switch HighlightsClos Theory: Cluster Scale Is the Driving Force for Data Center Network Architecture EvolutionSpineLeafCore EdgeSpineLeafCoreEdgeSpineLeafEdgeL2L310GE10GE40GE 40GE 40GEL2BGPL3L3First generation: 3K GE serversSecond generation: 10K GE serversThird generation: 20K 10GE servers⚫The port capacity of cards increases continuously, and CE switches canprovide 36*100GE ports.⚫To avoid HASH polarization, CE switches provide 128 ECMP paths.⚫Network congestion control: CE switches provide large buffer, and split a single flow into multiple ones to load balance them.Difficulties in the non-blocking Clos architecture: The convergence ratio and packet loss ratio cannot be compromised.⚫Data center network architecture: A fat-tree topology is used and the capacity of the root node determines the server cluster scale.⚫Evolution direction: Add network layers, and increase the quantity and capacity of spine or code nodes.⚫Network congestion control: Increase the buffer and optimize load balancing.CE switches' buffer is 80 times higher than the industry average, implementing zero packet loss for microburst traffic. The switches' performance is 1032 Tbit/s. CE switches can connect to over 50,000 servers with no blocking.Larger Interface Rate: The Rise of 25GE Interfaces Balance the Cost and Efficiency10M1980100M: IEEE802.3u199519981000M: IEEE802.3ab/z20021G: IEEE802.3ae/ak201040G/100G: IEEE802.3ba2008DCB/PB (IETF TRILL)2013400G2009FCoE201625G: 802.byDevelopment of Ethernet:DPDKIn the past two years, why are 25GE interfaces used?➢The 25GE interface can better match the SerDes rate: 1.25 Gbit/s -> 3.125 Gbit/s -> 6.25 Gbit/s -> 10.3125 Gbit/s -> 25 Gbit/s -> 56 Gbit/s➢Compared with the 40GE NIC, the 25GE NIC has higher use efficiency of the PCIe channel. (40G+40G)/8G*16= 62.5%; 25G*2/(8G*8) = 78%➢Lower cabling costs for 25GE interfaces: The SFP28 module is used. Because only single-channel connections are used, the SFP28 module is compatible with LC optical fibers in the 10GE era, without cabling.➢The bandwidth between NICs has exceeded 10 Gbit/s: As technologies such as RDMA, SR-IOV, and DPDK develop, the bandwidth between NICs has exceeded 10 Gbit/s.APP RDMA NICCoprocess or/FPGAAPPRDMA NICFast CNPCNPPPVIQ: eliminates packet lossinside chipsVIQ12Dynamic ECN3Dynamic ECNFast CNPPacket lossTraditionalVIQVIQ enables the outbound interface to send backpressure signals to the inbound interface, achieving zero packet loss.PFCSRECNNormal CNPPhysical queueThreshold (Port-Buffer)SwitchServer Q0Q1ECN waterline ECN waterlineRR ServerServerServer.. .Dynamic ECN uses dynamic collection and dynamic threshold adjustment to realize low latency and high throughput.Fast CNP provides fast congestion feedback to improve networkconvergence performance by 30%.AI Fabric: Intelligent Lossless Data Center Network Solution Provides Low latency and Zero Packet LossFast CNPUltra-broadband Cloud Engine Simplified Cloud Engine Intelligent Cloud Engine Secure CloudEngine Open Cloud Engine➢Independent forwarding, control, anddetection, and 3-channel cluster design ➢Four dedicated GE interfaces are used ascluster control channels.➢ A maximum of 3.2 Tbit/s cluster bandwidthis supported.Unique three-channel separated cluster, control plane coupling…Control signalingchannelData forwardingchannel Dual-active detection (DAD) channel➢The control plane runs independently and synchronizes asmall amount of information about interface status entries.➢Devices in the DFS group can be upgraded independently,without interrupting services.➢When the peer-link is faulty or the M-LAG master devicefails twice, the M-LAG backup device can still work properly.Independent control plane, protocol-level coupling…Peer-linkDAD channelDevice Virtualization: Easy-to-Manage, High-Performing, Highly Reliable Virtual SystemsC luster S witch S ystem (CSS)M ulti-Chassis LAG (M-LAG)➢The control plane runs independently anddoes not have synchronization information.➢Two switches are configured with the samegateway IP address and MAC address.➢Two links of the server NIC are configured tosend broadcast packets simultaneously.Independent control planewithout couplingM-LAG Lite➢Provide a maximum of 1:16virtualization capabilities in port and port group mode.On-demand VS allocation, improving resource utilization➢Exclusive CPU, memory, and MAC/VLAN/FIB entriesExclusive resources in VSs and highest specificationsFault isolation between VSs, improving securityVS (V irtual S ystem )Ultra-broadband Cloud Engine Simplified Cloud Engine Intelligent Cloud Engine Secure CloudEngine Open Cloud EngineLayer 2 Boundary Extension: Build a Large-Scale Network Resource Pool Based on BGP EVPNBGP EVPN acts as the VXLAN control plane to provide the following functions:➢Triggers automatic VXLAN tunnel setup between VTEPs to avoid the need to manually configure full-mesh tunnels.➢Advertises host routes and MAC address table, prevents unknown traffic flooding, and optimizes packet forwarding.➢Implements Layer 2 interconnection between data centers in different networking.Layer 2 large-scale horizontal expansion in the data centerand extension to the remote DCVXLAN BGP EVPNVTEP VTEP VTEP VTEP RRRRBGP EVPNVTEP VTEPProtocol vitality: open interconnection and interworkingbetween devices from different vendorsNetwork Automation: Interconnection with Third-Party Management Tools, Controllers, Virtualization Management Platforms, and Cloud PlatformsScenario 1: traditional network management➢Interconnection with a third-party management tool : CE switches can interconnect with a third-party management tool such as Ansible to implement automatic network configuration.Scenario 2: network and computing association➢Interconnection with a virtualization management platform : CE switches are connected to the Agile Controller-DCN, and the Agile Controller-DCN is associated with the third-party computing management platform.Scenario 3: third-party management on the overlay➢Interconnection with a third-party controller : The CE switch functions as the VXLAN Layer 2 VTEP and is managed by the NSX.Scenario 4: cloud-network integration➢Interconnection with a cloud platform through the Agile Controller-DCN : CE switches are connected to the AgileController-DCN, and the Agile Controller-DCN connects to the third-party cloud platform.SpineLeafGateway10GE40GEDCScenario 1Interconnection with a managementtoolISP2Scenario 2Interconnection with avirtualization managementplatformScenario 3Interconnectionwith a third-party controller Scenario 4Interconnection with a cloud platformSimplified Deployment: IPv4 and IPv6, Unicast and Overlay Multicast, and Rollout of Full-stack Services Within MinutesServer leaf IPv6IPv4VTEP Server leaf SpineVTEPServer leaf VM VM VMOVSBorder-LeafBMVTEP VM VM VMOVSServer leaf VTEPBMIPv4 extranetIPv4Service-centered IPv6 evolution mode➢2018 Q3: virtualization ➢2019 Q1: cloud-network cooperationServer leafIPv6IPv4VTEP Server leaf SpineVTEPServer leaf VM VM VMOVSBorder-LeafBMVTEP VM VM VMOVSServer leaf VTEPIPv6 extranetIPv4 extranetIPv4IPv6 extranetReplicate IPv4 O&MexperiencesServer leafVTEP Server leaf SpineVTEPServer leaf VM VM VMOVSBM VTEP VM VM VMOVSServer leaf VTEPIPv4 extranetIPv4 extranetOverlay multicastSave bandwidthServer leafVTEP Server leaf SpineVTEPServer leaf VM VM VMOVSBM VTEP VM VM VMOVSServer leaf VTEPIPv4 extranetIPv4 extranetDual-stackMulticastIngress replicationIGMP/PIM-SM➢2018 Q3: commercial chip ready ➢2019 Q1: controller mappingCollectorAnalyzerCPU Forwarding Chip CollectorAnalyzerCPUForwarding ChipCollectorAnalyzerCPUForwarding ChipNP•SNMP or NETCONF uses the query/response mechanism, minute-level reporting, and XML or text encoding, which is inefficient.•NetStream uses the flow sampling mechanism and requires CPU participation, which has low performance and is inaccurate.•gRPC uses the subscription/reporting mechanism, subsecond-level reporting , protobuffer coding, and HTTP transmission, which has a high efficiency .•ERSPAN+ adds ingress and egress ports or timestamps of original flows to calculate the flow path and delay .•INT supports in-line path or quality detection.SNMP NetconfNetstreamERSPANSNMP NetconfNetstreamERSPAN+INTgRPCSNMP NetconfFlow tableProtobuf over UDPgRPCERSPAN+Netstream1:1•Protobuf over UDP is used to encode andtransmit forwarding plane information, which is efficient and does not affect CPU performance .•Small NP intelligent analysis algorithm is used to perform in-depth analysis of abnormal flows to learn in-depth information such as the latency, jitter, packet loss ratio, and packet loss location .Historical CapabilitiesCurrent CapabilitiesFuture EvolutionTelemetry Capability: Transformation of the Data Collection Mode Is the Basis of Big Data O&MUltra-broadband Cloud Engine Simplified Cloud Engine Intelligent Cloud Engine Secure CloudEngine Open Cloud EngineMicroburst Detection Capability: Millisecond-level Buffer Monitoring and Subscription Collection, Which Are Visible and ClearData CenterService exceptionNormal networkTraditional NMSArtifactFreezeSubsecond-levelcollectiongRPC subscription . . .Content feedbackOne request formultiple tasks•Visible: subsecond-level subscription data collection510us50%100%The buffer is full and packet loss may occur.2-ms buffer monitoring•Clear: high-precision data monitoring5-minute pollingperiodSNMP request and response. . .Multiple requests for a single task510s50%100%Normal buffer detectionMicrosecond-level buffer monitoring•The collection period is too long, which may ignore network details.•The detection interval is too long, so device details may be incomplete.Forwarding chipCPUFPGACE8860Monitoring queueNote: The CE8860 supports this function.VM 1VM 2VM 3 1.1.1.1 1.1.1.2 1.1.1.3VM 4VM 5VM 6 2.2.2.1 2.2.2.2 2.2.2.3As Is: subnet-based isolation To Be:VM-level isolationFine-grained DefenseDefining applications based on VM names and discrete IP addresses, with finer granularity and wider dimensionsFlexible DeploymentDefining services based on application groups and decoupling from subnets to achieve flexible deployment Distributed SecurityTraffic of access switches is filtered nearby and east-west isolation is implemented without using firewalls.Use Microsegmentation to Achieve Fine-grained Isolation and Service SecurityWebAppAFW IDS LB NATVASResource poolSimplified deploymentThe SDN controller definesservice chains through drag-and-drop operations.Efficient forwardingProvide traffic diversion for one time, simple configuration, service traffic forwarding, and secure monitoring.Flexible orchestrationDecouple the VAS function from Fabric, providing flexible orchestration.Switch SwitchSwitchAgile CloudEngine: Supporting NSH Service Chains, Providing Easier VAS OrchestrationACOpticalfiber/transmissiondevice/Layer 2 transparenttransmissionMacSec at the Link Layer: IP Layer 3 Features such as Encryption Are Introduced to the MAC Link LayerSwitch ASwitch BScenario➢In scenarios that require high data confidentiality, such asgovernment, military, and finance scenarios, interconnection is required between data centers or between different modules of data centers across buildings.➢The CE6875 uplink port (100GE), and CEL16CQFD (16*100GE) and CEL08CFFG1 (8*200GE) cards of the CE12800 can be used.Definition➢Media Access Control Security (MACsec) ensures securecommunication within LANs in compliance with IEEE 802.1AE and 802.1X. It provides identity authentication, data encryption, integrity check, and replay protection to protect Ethernet frames and prevent devices from processing attack packets.NetworkingNetworkingOriginal packetData encryption protectionMACsec packetData integrity protectionStandardsChinaIntegration InnovationEcological cooperationGermany MoscowMulti-vendor pre-integration verificationMulti-layer open ecosystemOpen Ecosystem: Huawei Joins Hands with 20+ Industry Chain Partners to Perform System IntegrationOpen ecosystem: fast integration andsimplified managementSystem integration: 10+ OpenLabs in the globeManufacturerNSXAnsible. . .Rapid response to service requirementsHardware BFDMicrosegmentationNSH modeIPv6 over VXLANCPUForwarding chipIntra-card CPU chip Quad-core CPU:▪Protocol packet processing▪FIB entry delivery ▪. . .Co-processor▪Hardware BFD ▪High-performance sFlow ▪. . .Forwarding chipAdjustable processes New service processes Adjustable entry resourcesEnhanced serviceprocessesVRPnetconfCLILinux ContainergRPCopenflowSSHpuppetFuncEditnetconfSNMPLinux and driverFragmentation and reassemblyOpen architecture, Flexible Business Innovation•Higher interface rate: 25GE interfaces and larger buffer cope with traffic surge in N:1 scenarios.•Flowlet&DLB: One flow is load balanced among multiple links.•AI Fabric intelligent lossless data center network solution: low latency and zero packet lossUltra-broadband: higher interface rate, more even load balancing, larger buffer, and lower latency•Telemetry capability•Microburst detection •Edge analysis capability•Microsegmentation used to isolate east-west traffic on switches (east-west traffic is isolated on firewalls originally)•SFC used to divert traffic from the control plane to the data plane•MACsec hardware encryption, providing high security and reliability•Open API•Interconnection with third-party management tools: Ansible•Interconnection with third-party management tools or controllers: VMaare NSX•Multiple virtualization technologies: CSS, M-LAG, M-LAG Lite, and VS •VXLAN + BGP EVPN: intra-DC and inter-DC virtualization•SDN controller: deployment in drag-and-drop mode, IPv4 and IPv6, rollout of unicast and multicast full-stack services in minutesIntelligent: enabling service agilitySimplified: automatic deployment of full-stack services and service rollout within minutesOpen: easy integration and timelyresponse to servicesSecure: best quality in the industry and pioneering energy-saving technology CloudEngine High-Performance Cloud SwitchesContents1Click to add Title 2CloudEngine Switch OverviewCloudEngine Switch Highlights Click to add Title 3CloudEngine Switch Market ProgressChina's No.1 and One of World's Top 3 DCN Vendors2014Source: IHS “2015 Infonetics Data Center and Enterprise SDN Vendor Leadership Analysis ”20132012•Data center network vendor with the fastest growth•First release of InterOP impressing the world •Industry-leading ultra-high performance2015•Huawei was the only Chinese vendor in the global SDN leadership list.•Largest market share in China in Q2•Huawei was the global data center network vendor with the fastest growth.•Annual growth rate up to 137%Global SDN AuthoritativeReport of Leading Vendors2016•The market share ranks No. 1 in Chi na and the third largest in the world .•SDN capability won the Best of ShowNet Award at Tokyo Interop.2017•Huawei was positioned as challenger in Gartner's Magic Quadrant for Data Center Networking.2018•Huawei has been positioned as a leader in data center hardware platforms for SDN.•The AI Fabric won the Best of Show Gold Award.In 2013, the CloudEngine 12800 won the Best of Show Award at Interop, which is the highest exhibition in the IT industry. Huawei is the first Chinese provider that wins the position.Highly Recognized PerformanceAward of Excellent Product Trusted byCIOAward of the Most Competitive Product Awards and CertificationsPreferred Brand of Cloud Computing and Network SolutionAward of Annual Excellent TechnologyChina SDN SDN Best Practice AwardAward of Excellent Product in Big DataIn 2016, the CE8860 and CE6851 won the Best of Show Award at Interop.InterOP AwardsHuawei's AI FabricIntelligent Lossless Data Center Network Solution Takes Home Interop Tokyo Best of Show AwardCloudEngineSeries Switches Serve 7800+ Global Customers⚫The market share is No.1in China and No.3in theworld.⚫The global market share growth rate is No. 1 for fourconsecutive years .⚫Over 32,000 CE12800 switches have been soldaround the world, serving 7800+customers in 120+countries.DC SDN SDN hardware platform leader⚫2018 Approaching the Leaders Quadrant ⚫2017 ChallengerGartner Peer InsightsCustomers’ Choice for Data Center NetworkingCopyright©2018 Huawei Technologies Co., Ltd.All Rights Reserved.The information in this document may contain predictivestatements including, without limitation, statements regarding the future financial and operating results, future productportfolio, new technology, etc. There are a number of factors that could cause actual results and developments to differ materially from those expressed or implied in the predictive statements. Therefore, such information is provided for reference purpose only and constitutes neither an offer nor an acceptance. Huawei may change the information at any time without notice.把数字世界带入每个人、每个家庭、每个组织，构建万物互联的智能世界。
数字无线通信系统中的调制(英文)
AgilentDigital Modulation in Communications Systems—An IntroductionApplication Note 1298This application note introduces the concepts of digital modulation used in many communications systems today. Emphasis is placed on explaining the tradeoffs that are made to optimize efficiencies in system design.Most communications systems fall into one of three categories: bandwidth efficient, power efficient, or cost efficient. Bandwidth efficiency describes the ability of a modulation scheme to accommodate data within a limited bandwidth. Power efficiency describes the ability of the system to reliably send information at the lowest practical power level.In most systems, there is a high priority on band-width efficiency. The parameter to be optimized depends on the demands of the particular system, as can be seen in the following two examples.For designers of digital terrestrial microwave radios, their highest priority is good bandwidth efficiency with low bit-error-rate. They have plenty of power available and are not concerned with power efficiency. They are not especially con-cerned with receiver cost or complexity because they do not have to build large numbers of them. On the other hand, designers of hand-held cellular phones put a high priority on power efficiency because these phones need to run on a battery. Cost is also a high priority because cellular phones must be low-cost to encourage more users. Accord-ingly, these systems sacrifice some bandwidth efficiency to get power and cost efficiency. Every time one of these efficiency parameters (bandwidth, power, or cost) is increased, another one decreases, becomes more complex, or does not perform well in a poor environment. Cost is a dom-inant system priority. Low-cost radios will always be in demand. In the past, it was possible to make a radio low-cost by sacrificing power and band-width efficiency. This is no longer possible. The radio spectrum is very valuable and operators who do not use the spectrum efficiently could lose their existing licenses or lose out in the competition for new ones. These are the tradeoffs that must be considered in digital RF communications design. This application note covers•the reasons for the move to digital modulation;•how information is modulated onto in-phase (I) and quadrature (Q) signals;•different types of digital modulation;•filtering techniques to conserve bandwidth; •ways of looking at digitally modulated signals;•multiplexing techniques used to share the transmission channel;•how a digital transmitter and receiver work;•measurements on digital RF communications systems;•an overview table with key specifications for the major digital communications systems; and •a glossary of terms used in digital RF communi-cations.These concepts form the building blocks of any communications system. If you understand the building blocks, then you will be able to under-stand how any communications system, present or future, works.Introduction25 5 677 7 8 8 9 10 10 1112 12 12 13 14 14 15 15 16 17 18 19 20 21 22 22 23 23 24 25 26 27 28 29 29 30 311. Why Digital Modulation?1.1 Trading off simplicity and bandwidth1.2 Industry trends2. Using I/Q Modulation (Amplitude and Phase Control) to Convey Information2.1 Transmitting information2.2 Signal characteristics that can be modified2.3 Polar display—magnitude and phase representedtogether2.4 Signal changes or modifications in polar form2.5 I/Q formats2.6 I and Q in a radio transmitter2.7 I and Q in a radio receiver2.8 Why use I and Q?3. Digital Modulation Types and Relative Efficiencies3.1 Applications3.1.1 Bit rate and symbol rate3.1.2 Spectrum (bandwidth) requirements3.1.3 Symbol clock3.2 Phase Shift Keying (PSK)3.3 Frequency Shift Keying3.4 Minimum Shift Keying (MSK)3.5 Quadrature Amplitude Modulation (QAM)3.6 Theoretical bandwidth efficiency limits3.7 Spectral efficiency examples in practical radios3.8 I/Q offset modulation3.9 Differential modulation3.10 Constant amplitude modulation4. Filtering4.1 Nyquist or raised cosine filter4.2 Transmitter-receiver matched filters4.3 Gaussian filter4.4 Filter bandwidth parameter alpha4.5 Filter bandwidth effects4.6 Chebyshev equiripple FIR (finite impulse response) filter4.7 Spectral efficiency versus power consumption5. Different Ways of Looking at a Digitally Modulated Signal Time and Frequency Domain View5.1 Power and frequency view5.2 Constellation diagrams5.3 Eye diagrams5.4 Trellis diagramsTable of Contents332 32 32 33 33 34 3435 35 3637 37 37 38 38 39 39 39 40 41 41 42 434344466. Sharing the Channel6.1 Multiplexing—frequency6.2 Multiplexing—time6.3 Multiplexing—code6.4 Multiplexing—geography6.5 Combining multiplexing modes6.6 Penetration versus efficiency7. How Digital Transmitters and Receivers Work7.1 A digital communications transmitter7.2 A digital communications receiver8. Measurements on Digital RF Communications Systems 8.1 Power measurements8.1.1 Adjacent Channel Power8.2 Frequency measurements8.2.1 Occupied bandwidth8.3 Timing measurements8.4 Modulation accuracy8.5 Understanding Error Vector Magnitude (EVM)8.6 Troubleshooting with error vector measurements8.7 Magnitude versus phase error8.8 I/Q phase error versus time8.9 Error Vector Magnitude versus time8.10 Error spectrum (EVM versus frequency)9. Summary10. Overview of Communications Systems11. Glossary of TermsTable of Contents (continued)4The move to digital modulation provides more information capacity, compatibility with digital data services, higher data security, better quality communications, and quicker system availability. Developers of communications systems face these constraints:•available bandwidth•permissible power•inherent noise level of the systemThe RF spectrum must be shared, yet every day there are more users for that spectrum as demand for communications services increases. Digital modulation schemes have greater capacity to con-vey large amounts of information than analog mod-ulation schemes. 1.1 Trading off simplicity and bandwidthThere is a fundamental tradeoff in communication systems. Simple hardware can be used in transmit-ters and receivers to communicate information. However, this uses a lot of spectrum which limits the number of users. Alternatively, more complex transmitters and receivers can be used to transmit the same information over less bandwidth. The transition to more and more spectrally efficient transmission techniques requires more and more complex hardware. Complex hardware is difficult to design, test, and build. This tradeoff exists whether communication is over air or wire, analog or digital.Figure 1. The Fundamental Tradeoff1. Why Digital Modulation?51.2 Industry trendsOver the past few years a major transition has occurred from simple analog Amplitude Mod-ulation (AM) and Frequency/Phase Modulation (FM/PM) to new digital modulation techniques. Examples of digital modulation include•QPSK (Quadrature Phase Shift Keying)•FSK (Frequency Shift Keying)•MSK (Minimum Shift Keying)•QAM (Quadrature Amplitude Modulation) Another layer of complexity in many new systems is multiplexing. Two principal types of multiplex-ing (or “multiple access”) are TDMA (Time Division Multiple Access) and CDMA (Code Division Multiple Access). These are two different ways to add diversity to signals allowing different signals to be separated from one another.Figure 2. Trends in the Industry62.1 Transmitting informationTo transmit a signal over the air, there are three main steps:1.A pure carrier is generated at the transmitter.2.The carrier is modulated with the informationto be transmitted. Any reliably detectablechange in signal characteristics can carryinformation.3.At the receiver the signal modifications orchanges are detected and demodulated.2.2 Signal characteristics that can be modified There are only three characteristics of a signal that can be changed over time: amplitude, phase, or fre-quency. However, phase and frequency are just dif-ferent ways to view or measure the same signal change. In AM, the amplitude of a high-frequency carrier signal is varied in proportion to the instantaneous amplitude of the modulating message signal.Frequency Modulation (FM) is the most popular analog modulation technique used in mobile com-munications systems. In FM, the amplitude of the modulating carrier is kept constant while its fre-quency is varied by the modulating message signal.Amplitude and phase can be modulated simultane-ously and separately, but this is difficult to gener-ate, and especially difficult to detect. Instead, in practical systems the signal is separated into another set of independent components: I(In-phase) and Q(Quadrature). These components are orthogonal and do not interfere with each other.Figure 3. Transmitting Information (Analog or Digital)Figure 4. Signal Characteristics to Modify2. Using I/Q Modulation to Convey Information72.3 Polar display—magnitude and phase repre-sented togetherA simple way to view amplitude and phase is with the polar diagram. The carrier becomes a frequency and phase reference and the signal is interpreted relative to the carrier. The signal can be expressed in polar form as a magnitude and a phase. The phase is relative to a reference signal, the carrier in most communication systems. The magnitude is either an absolute or relative value. Both are used in digital communication systems. Polar diagrams are the basis of many displays used in digital com-munications, although it is common to describe the signal vector by its rectangular coordinates of I (In-phase) and Q(Quadrature).2.4 Signal changes or modifications inpolar formFigure 6 shows different forms of modulation in polar form. Magnitude is represented as the dis-tance from the center and phase is represented as the angle.Amplitude modulation (AM) changes only the magnitude of the signal. Phase modulation (PM) changes only the phase of the signal. Amplitude and phase modulation can be used together. Frequency modulation (FM) looks similar to phase modulation, though frequency is the controlled parameter, rather than relative phase.Figure 6. Signal Changes or Modifications8One example of the difficulties in RF design can be illustrated with simple amplitude modulation. Generating AM with no associated angular modula-tion should result in a straight line on a polar display. This line should run from the origin to some peak radius or amplitude value. In practice, however, the line is not straight. The amplitude modulation itself often can cause a small amount of unwanted phase modulation. The result is a curved line. It could also be a loop if there is any hysteresis in the system transfer function. Some amount of this distortion is inevitable in any sys-tem where modulation causes amplitude changes. Therefore, the degree of effective amplitude modu-lation in a system will affect some distortion parameters.2.5 I/Q formatsIn digital communications, modulation is often expressed in terms of I and Q. This is a rectangular representation of the polar diagram. On a polar diagram, the I axis lies on the zero degree phase reference, and the Q axis is rotated by 90 degrees. The signal vector’s projection onto the I axis is its “I” component and the projection onto the Q axisis its “Q” component.Figure 7. “I-Q” Format92.6 I and Q in a radio transmitterI/Q diagrams are particularly useful because they mirror the way most digital communications sig-nals are created using an I/Q modulator. In the transmitter, I and Q signals are mixed with the same local oscillator (LO). A 90 degree phase shifter is placed in one of the LO paths. Signals that are separated by 90 degrees are also known as being orthogonal to each other or in quadrature. Signals that are in quadrature do not interfere with each other. They are two independent compo-nents of the signal. When recombined, they are summed to a composite output signal. There are two independent signals in I and Q that can be sent and received with simple circuits. This simpli-fies the design of digital radios. The main advan-tage of I/Q modulation is the symmetric ease of combining independent signal components into a single composite signal and later splitting such a composite signal into its independent component parts. 2.7 I and Q in a radio receiverThe composite signal with magnitude and phase (or I and Q) information arrives at the receiver input. The input signal is mixed with the local oscillator signal at the carrier frequency in two forms. One is at an arbitrary zero phase. The other has a 90 degree phase shift. The composite input signal (in terms of magnitude and phase) is thus broken into an in-phase, I, and a quadrature, Q, component. These two components of the signal are independent and orthogonal. One can be changed without affecting the other. Normally, information cannot be plotted in a polar format and reinterpreted as rectangular values without doing a polar-to-rectangular conversion. This con-version is exactly what is done by the in-phase and quadrature mixing processes in a digital radio. A local oscillator, phase shifter, and two mixers can perform the conversion accurately and efficiently.Figure 8. I and Q in a Practical Radio Transmitter Figure 9. I and Q in a Radio Receiver102.8 Why use I and Q?Digital modulation is easy to accomplish with I/Q modulators. Most digital modulation maps the data to a number of discrete points on the I/Q plane. These are known as constellation points. As the sig-nal moves from one point to another, simultaneous amplitude and phase modulation usually results. To accomplish this with an amplitude modulator and a phase modulator is difficult and complex. It is also impossible with a conventional phase modu-lator. The signal may, in principle, circle the origin in one direction forever, necessitating infinite phase shifting capability. Alternatively, simultaneous AM and Phase Modulation is easy with an I/Q modulator. The I and Q control signals are bounded, but infi-nite phase wrap is possible by properly phasing the I and Q signals.This section covers the main digital modulation formats, their main applications, relative spectral efficiencies, and some variations of the main modulation types as used in practical systems. Fortunately, there are a limited number of modula-tion types which form the building blocks of any system.3.1 ApplicationsThe table below covers the applications for differ-ent modulation formats in both wireless communi-cations and video. Although this note focuses on wireless communica-tions, video applications have also been included in the table for completeness and because of their similarity to other wireless communications.3.1.1 Bit rate and symbol rateTo understand and compare different modulation format efficiencies, it is important to first under-stand the difference between bit rate and symbol rate. The signal bandwidth for the communications channel needed depends on the symbol rate, not on the bit rate.Symbol rate =bit ratethe number of bits transmitted with each symbol 3. Digital Modulation Types and Relative EfficienciesBit rate is the frequency of a system bit stream. Take, for example, a radio with an 8 bit sampler, sampling at 10 kHz for voice. The bit rate, the basic bit stream rate in the radio, would be eight bits multiplied by 10K samples per second, or 80 Kbits per second. (For the moment we will ignore the extra bits required for synchronization, error correction, etc.)Figure 10 is an example of a state diagram of a Quadrature Phase Shift Keying (QPSK) signal. The states can be mapped to zeros and ones. This is a common mapping, but it is not the only one. Any mapping can be used.The symbol rate is the bit rate divided by the num-ber of bits that can be transmitted with each sym-bol. If one bit is transmitted per symbol, as with BPSK, then the symbol rate would be the same as the bit rate of 80 Kbits per second. If two bits are transmitted per symbol, as in QPSK, then the sym-bol rate would be half of the bit rate or 40 Kbits per second. Symbol rate is sometimes called baud rate. Note that baud rate is not the same as bit rate. These terms are often confused. If more bits can be sent with each symbol, then the same amount of data can be sent in a narrower spec-trum. This is why modulation formats that are more complex and use a higher number of states can send the same information over a narrower piece of the RF spectrum.3.1.2 Spectrum (bandwidth) requirementsAn example of how symbol rate influences spec-trum requirements can be seen in eight-state Phase Shift Keying (8PSK). It is a variation of PSK. There are eight possible states that the signal can transi-tion to at any time. The phase of the signal can take any of eight values at any symbol time. Since 23= 8, there are three bits per symbol. This means the symbol rate is one third of the bit rate. This is relatively easy to decode.Figure 10. Bit Rate and Symbol Rate Figure 11. Spectrum Requirements3.1.3 Symbol ClockThe symbol clock represents the frequency and exact timing of the transmission of the individual symbols. At the symbol clock transitions, the trans-mitted carrier is at the correct I/Q(or magnitude/ phase) value to represent a specific symbol (a specific point in the constellation).3.2 Phase Shift KeyingOne of the simplest forms of digital modulation is binary or Bi-Phase Shift Keying (BPSK). One appli-cation where this is used is for deep space teleme-try. The phase of a constant amplitude carrier sig-nal moves between zero and 180 degrees. On an I and Q diagram, the I state has two different values. There are two possible locations in the state dia-gram, so a binary one or zero can be sent. The symbol rate is one bit per symbol.A more common type of phase modulation is Quadrature Phase Shift Keying (QPSK). It is used extensively in applications including CDMA (Code Division Multiple Access) cellular service, wireless local loop, Iridium (a voice/data satellite system) and DVB-S (Digital Video Broadcasting — Satellite). Quadrature means that the signal shifts between phase states which are separated by 90 degrees. The signal shifts in increments of 90 degrees from 45 to 135, –45, or –135 degrees. These points are chosen as they can be easily implemented using an I/Q modulator. Only two I values and two Q values are needed and this gives two bits per symbol. There are four states because 22= 4. It is therefore a more bandwidth-efficient type of modulation than BPSK, potentially twice as efficient.Figure 12. Phase Shift Keying3.3 Frequency Shift KeyingFrequency modulation and phase modulation are closely related. A static frequency shift of +1 Hz means that the phase is constantly advancing at the rate of 360 degrees per second (2 πrad/sec), relative to the phase of the unshifted signal.FSK (Frequency Shift Keying) is used in many applications including cordless and paging sys-tems. Some of the cordless systems include DECT (Digital Enhanced Cordless Telephone) and CT2 (Cordless Telephone 2).In FSK, the frequency of the carrier is changed as a function of the modulating signal (data) being transmitted. Amplitude remains unchanged. In binary FSK (BFSK or 2FSK), a “1” is represented by one frequency and a “0” is represented by another frequency.3.4 Minimum Shift KeyingSince a frequency shift produces an advancing or retarding phase, frequency shifts can be detected by sampling phase at each symbol period. Phase shifts of (2N + 1) π/2radians are easily detected with an I/Q demodulator. At even numbered sym-bols, the polarity of the I channel conveys the transmitted data, while at odd numbered symbols the polarity of the Q channel conveys the data. This orthogonality between I and Q simplifies detection algorithms and hence reduces power con-sumption in a mobile receiver. The minimum fre-quency shift which yields orthogonality of I and Q is that which results in a phase shift of ±π/2radi-ans per symbol (90 degrees per symbol). FSK with this deviation is called MSK (Minimum Shift Keying). The deviation must be accurate in order to generate repeatable 90 degree phase shifts. MSK is used in the GSM (Global System for Mobile Communications) cellular standard. A phase shift of +90 degrees represents a data bit equal to “1,”while –90 degrees represents a “0.” The peak-to-peak frequency shift of an MSK signal is equal to one-half of the bit rate.FSK and MSK produce constant envelope carrier signals, which have no amplitude variations. This is a desirable characteristic for improving the power efficiency of transmitters. Amplitude varia-tions can exercise nonlinearities in an amplifier’s amplitude-transfer function, generating spectral regrowth, a component of adjacent channel power. Therefore, more efficient amplifiers (which tend to be less linear) can be used with constant-envelope signals, reducing power consumption.Figure 13. Frequency Shift KeyingMSK has a narrower spectrum than wider devia-tion forms of FSK. The width of the spectrum is also influenced by the waveforms causing the fre-quency shift. If those waveforms have fast transi-tions or a high slew rate, then the spectrumof the transmitter will be broad. In practice, the waveforms are filtered with a Gaussian filter, resulting in a narrow spectrum. In addition, the Gaussian filter has no time-domain overshoot, which would broaden the spectrum by increasing the peak deviation. MSK with a Gaussian filter is termed GMSK (Gaussian MSK).3.5 Quadrature Amplitude ModulationAnother member of the digital modulation family is Quadrature Amplitude Modulation (QAM). QAM is used in applications including microwave digital radio, DVB-C (Digital Video Broadcasting—Cable), and modems.In 16-state Quadrature Amplitude Modulation (16QAM), there are four I values and four Q values. This results in a total of 16 possible states for the signal. It can transition from any state to any other state at every symbol time. Since 16 = 24, four bits per symbol can be sent. This consists of two bits for I and two bits for Q. The symbol rate is one fourth of the bit rate. So this modulation format produces a more spectrally efficient transmission. It is more efficient than BPSK, QPSK, or 8PSK. Note that QPSK is the same as 4QAM.Another variation is 32QAM. In this case there are six I values and six Q values resulting in a total of 36 possible states (6x6=36). This is too many states for a power of two (the closest power of two is 32). So the four corner symbol states, which take the most power to transmit, are omitted. This reduces the amount of peak power the transmitter has to generate. Since 25= 32, there are five bits per sym-bol and the symbol rate is one fifth of the bit rate. The current practical limits are approximately256QAM, though work is underway to extend the limits to 512 or 1024 QAM. A 256QAM system uses 16 I-values and 16 Q-values, giving 256 possible states. Since 28= 256, each symbol can represent eight bits. A 256QAM signal that can send eight bits per symbol is very spectrally efficient. However, the symbols are very close together and are thus more subject to errors due to noise and distortion. Such a signal may have to be transmit-ted with extra power (to effectively spread the symbols out more) and this reduces power efficiency as compared to simpler schemes.Figure 14. Quadrature Amplitude ModulationCompare the bandwidth efficiency when using256QAM versus BPSK modulation in the radio example in section 3.1.1 (which uses an eight-bit sampler sampling at 10 kHz for voice). BPSK uses80 Ksymbols-per-second sending 1 bit per symbol.A system using 256QAM sends eight bits per sym-bol so the symbol rate would be 10 Ksymbols per second. A 256QAM system enables the same amount of information to be sent as BPSK using only one eighth of the bandwidth. It is eight times more bandwidth efficient. However, there is a tradeoff. The radio becomes more complex and is more susceptible to errors caused by noise and dis-tortion. Error rates of higher-order QAM systems such as this degrade more rapidly than QPSK as noise or interference is introduced. A measureof this degradation would be a higher Bit Error Rate (BER).In any digital modulation system, if the input sig-nal is distorted or severely attenuated the receiver will eventually lose symbol lock completely. If the receiver can no longer recover the symbol clock, it cannot demodulate the signal or recover any infor-mation. With less degradation, the symbol clock can be recovered, but it is noisy, and the symbol locations themselves are noisy. In some cases, a symbol will fall far enough away from its intended position that it will cross over to an adjacent posi-tion. The I and Q level detectors used in the demodulator would misinterpret such a symbol as being in the wrong location, causing bit errors. QPSK is not as efficient, but the states are much farther apart and the system can tolerate a lot more noise before suffering symbol errors. QPSK has no intermediate states between the four corner-symbol locations, so there is less opportunity for the demodulator to misinterpret symbols. QPSK requires less transmitter power than QAM to achieve the same bit error rate.3.6 Theoretical bandwidth efficiency limits Bandwidth efficiency describes how efficiently the allocated bandwidth is utilized or the ability of a modulation scheme to accommodate data, within a limited bandwidth. The table below shows the theoretical bandwidth efficiency limits for the main modulation types. Note that these figures cannot actually be achieved in practical radios since they require perfect modulators, demodula-tors, filter, and transmission paths.If the radio had a perfect (rectangular in the fre-quency domain) filter, then the occupied band-width could be made equal to the symbol rate.Techniques for maximizing spectral efficiency include the following:•Relate the data rate to the frequency shift (as in GSM).•Use premodulation filtering to reduce the occupied bandwidth. Raised cosine filters,as used in NADC, PDC, and PHS, give thebest spectral efficiency.•Restrict the types of transitions.Modulation Theoretical bandwidthformat efficiencylimitsMSK 1bit/second/HzBPSK 1bit/second/HzQPSK 2bits/second/Hz8PSK 3bits/second/Hz16 QAM 4 bits/second/Hz32 QAM 5 bits/second/Hz64 QAM 6 bits/second/Hz256 QAM 8 bits/second/HzEffects of going through the originTake, for example, a QPSK signal where the normalized value changes from 1, 1 to –1, –1. When changing simulta-neously from I and Q values of +1 to I and Q values of –1, the signal trajectory goes through the origin (the I/Q value of 0,0). The origin represents 0 carrier magnitude. A value of 0 magnitude indicates that the carrier amplitude is 0 for a moment.Not all transitions in QPSK result in a trajectory that goes through the origin. If I changes value but Q does not (or vice-versa) the carrier amplitude changes a little, but it does not go through zero. Therefore some symbol transi-tions will result in a small amplitude variation, while others will result in a very large amplitude variation. The clock-recovery circuit in the receiver must deal with this ampli-tude variation uncertainty if it uses amplitude variations to align the receiver clock with the transmitter clock. Spectral regrowth does not automatically result from these trajectories that pass through or near the origin. If the amplifier and associated circuits are perfectly linear, the spectrum (spectral occupancy or occupied bandwidth) will be unchanged. The problem lies in nonlinearities in the circuits.A signal which changes amplitude over a very large range will exercise these nonlinearities to the fullest extent. These nonlinearities will cause distortion products. In con-tinuously modulated systems they will cause “spectral regrowth” or wider modulation sidebands (a phenomenon related to intermodulation distortion). Another term which is sometimes used in this context is “spectral splatter.”However this is a term that is more correctly used in asso-ciation with the increase in the bandwidth of a signal caused by pulsing on and off.3.7 Spectral efficiency examples inpractical radiosThe following examples indicate spectral efficien-cies that are achieved in some practical radio systems.The TDMA version of the North American Digital Cellular (NADC) system, achieves a 48 Kbits-per-second data rate over a 30 kHz bandwidth or 1.6 bits per second per Hz. It is a π/4 DQPSK based system and transmits two bits per symbol. The theoretical efficiency would be two bits per second per Hz and in practice it is 1.6 bits per second per Hz.Another example is a microwave digital radio using 16QAM. This kind of signal is more susceptible to noise and distortion than something simpler such as QPSK. This type of signal is usually sent over a direct line-of-sight microwave link or over a wire where there is very little noise and interference. In this microwave-digital-radio example the bit rate is 140 Mbits per second over a very wide bandwidth of 52.5 MHz. The spectral efficiency is 2.7 bits per second per Hz. To implement this, it takes a very clear line-of-sight transmission path and a precise and optimized high-power transceiver.。
描述机房的英语作文
描述机房的英语作文英文回答：The data center, the heart of modern digital infrastructure, is a highly specialized facility designed to house and support the critical IT systems and data that power today's businesses and organizations. Thesefacilities are typically purpose-built to provide a secure, reliable, and energy-efficient environment for the operation and maintenance of servers, storage devices, networking equipment, and other essential components.One of the most notable characteristics of a data center is its high level of physical security. To protect against unauthorized access and potential threats, data centers employ multiple layers of security measures, including access control systems, video surveillance, intrusion detection, and perimeter fencing. Controlled access points, biometric identification, and specialized security personnel ensure that only authorized individualscan enter the facility.Another crucial aspect of data center design is the provision of a stable and reliable power supply. Redundant power systems, including backup generators anduninterruptible power supplies (UPS), are implemented to ensure that critical IT equipment remains operational evenin the event of a power outage. Precision cooling systems, such as air conditioning units and liquid cooling technologies, are also employed to maintain optimal operating temperatures and prevent equipment overheating.To meet the ever-increasing demand for data storage and processing, data centers utilize high-density server racks and blade servers that maximize space utilization andenergy efficiency. These racks typically accommodatemultiple servers within a single enclosure, allowing for efficient cable management and reduced cooling requirements.Furthermore, data centers implement advanced network connectivity and high-speed data transfer capabilities to facilitate seamless communication between servers andstorage devices. Fiber optic cables, high-bandwidth switches, and load balancers ensure rapid and reliable data transmission, enabling the efficient handling of large volumes of information.In addition to security, power, and network infrastructure, modern data centers also prioritize environmental sustainability. Energy-efficient designs, such as virtualization technologies and power-saving cooling systems, help reduce energy consumption and minimize the facility's carbon footprint. Sustainable practices, including recycling programs and responsible waste management, are also implemented to promote environmental responsibility.中文回答：机房。
j3160
j3160J3160: A Comprehensive OverviewIntroduction:The J3160 is an advanced processor that is part of the Intel® Celeron® family. It offers a range of powerful features and capabilities, making it a popular choice for various computing applications. In this document, we will delve into the architecture, specifications, performance, and use cases of the J3160 processor.1. Architecture:The J3160 processor is built on Intel's advanced 14nm manufacturing process, ensuring superior power efficiency and performance. Its architecture consists of four cores and four threads, allowing for efficient multitasking. The base clock speed of the processor is 1.60 GHz, with a maximum turbo frequency of 2.24 GHz. This ensures fast and responsive computing across various applications.2. Specifications:The J3160 processor offers a range of impressive specifications that contribute to its overall performance. It has a TDP (thermal design power) of 6 watts, which enables it to deliver excellent performance while maintaining low power consumption. The processor supports DDR3L and LPDDR3 memory with a maximum capacity of 8GB, providing ample memory bandwidth for smooth operation.3. Performance:The J3160 processor delivers reliable performance, making it suitable for a wide range of computing tasks. Its multi-core architecture enables efficient multitasking, ensuring smooth performance even during resource-intensive activities. The processor's integrated Intel® HD Graphics unit enhances visual experiences and enables the handling of graphics-intensive tasks with ease.When it comes to everyday computing tasks such as web browsing, word processing, and media consumption, theJ3160 processor performs admirably. It offers excellent responsiveness and seamless multitasking, allowing for smooth user experience.4. Use Cases:The J3160 processor finds applications in various computing domains, ranging from entry-level desktops and all-in-one PCs to compact industrial systems. Its low power consumption and robust performance make it an ideal choice for environments where both energy efficiency and reliability are crucial.The processor's graphics capabilities make it suitable for media streaming, casual gaming, and light video editing tasks. Its efficient architecture also supports smooth handling of multimedia playback, ensuring high-quality visual experiences.In industrial settings, the J3160 processor proves its worth by powering compact systems used in automation, surveillance, and embedded computing applications. Its low power consumption and compact size make it an excellent choice for space-constrained environments.5. Connectivity and Features:The J3160 processor supports a range of connectivity options, including USB 3.0, SATA 6 Gbps, and PCIe Gen2. These features enable quick data transfer and facilitate the integration of modern peripherals and storage devices.Moreover, the processor supports Intel® Virtualization Technology (Intel® VT-x), which enhances system security and allows for the efficient utilization of computing resources.Conclusion:In summary, the J3160 processor from Intel® Celeron® family offers a combination of powerful performance, low power consumption, and reliable multitasking. Its architecture, specifications, and features make it an excellent choice for various computing applications, including entry-level desktops, all-in-one PCs, compact industrial systems, and media streaming devices.With its advanced technology and efficient architecture, theJ3160 processor is a reliable solution that delivers exceptional performance and enhances user experiences. Whether it's for everyday computing tasks or demanding industrial applications, the J3160 processor is sure to meet the requirements of diverse computing needs.。
节点方案英文
节点方案英文Node SchemeIntroductionIn today's rapidly evolving technological landscape, the need for efficient and reliable networks is paramount. One crucial aspect of designing a network is determining the appropriate node scheme. A node scheme refers to the arrangement and configuration of network nodes, which are the essential building blocks of any network infrastructure. This article aims to explore the fundamental principles and considerations involved in devising a node scheme, focusing on key aspects such as scalability, redundancy, and network optimization.ScalabilityScalability is a vital factor when it comes to designing a node scheme. It refers to the network's ability to handle an increasing workload and expand in response to growing demands. To achieve scalability, a node scheme should incorporate modular architectures that allow for easy addition or removal of nodes without disrupting the entire network. Additionally, the use of virtualization technologies, such as cloud computing, can enhance scalability by enabling seamless resource allocation and management.RedundancyEnsuring network reliability is another crucial aspect of a well-designed node scheme. Redundancy, which involves duplicating network components, plays a significant role in achieving this goal. By incorporating redundantnodes, failures or disruptions in one part of the network can be mitigated as traffic is rerouted through alternative paths. Redundancy can be achieved at various levels, including hardware redundancy, where multiple physical devices are deployed, and software redundancy, which involves implementing failover mechanisms and backup systems.Network OptimizationOptimizing network performance is a key objective of any node scheme. This involves fine-tuning various parameters to ensure efficient data transmission and minimize latency. An effective node scheme should consider factors such as bandwidth allocation, routing protocols, and network traffic management. By applying load balancing techniques, network administrators can evenly distribute the workload across nodes, preventing bottlenecks and optimizing overall performance.Security ConsiderationsWhen designing a node scheme, security should be paramount. In an interconnected world, networks are vulnerable to various threats, such as unauthorized access, data breaches, and malware attacks. Implementing robust security measures, including authentication mechanisms, encryption protocols, and intrusion detection systems, is essential to safeguard network integrity. The node scheme should take into account these security considerations and provide a framework for secure data transmission and protection against potential threats.Case Study: Enterprise NetworkTo better understand the practical implementation of a node scheme, let's consider a case study of an enterprise network. In this scenario, the node scheme should cater to the organization's specific requirements, such as seamless communication, data exchange, and resource sharing.The node scheme for an enterprise network might consist of a centralized hub, where critical services and central data repositories are located. From this central hub, various branches or remote locations can be connected through distributed nodes, ensuring efficient communication and data synchronization. The deployment of redundant nodes at critical points within the network provides resilience and fault tolerance, minimizing downtime and ensuring business continuity.ConclusionIn conclusion, a well-designed node scheme is fundamental to building a robust and efficient network infrastructure. By considering scalability, redundancy, network optimization, and security, network architects can develop a node scheme that meets the specific requirements of any organization or application. Understanding the intricacies of node schemes is crucial in today's interconnected world, where networks are the backbone of modern communication and information exchange.。
英语作文-探索集成电路设计中的新技术与应用前景
英语作文-探索集成电路设计中的新技术与应用前景As integrated circuit (IC) design continues to evolve, new technologies are constantly emerging, offering exciting possibilities for innovation and advancement. In this essay, we will explore some of the latest trends and applications in IC design, highlighting their potential impact on various industries and the future landscape of technology.One of the most significant advancements in IC design is the development of 3D integration technology. Unlike traditional 2D designs, which place all components on a single plane, 3D integration allows for stacking multiple layers of integrated circuits, thereby increasing functionality and performance while reducing footprint. This technology enables the creation of smaller, more power-efficient devices, making it ideal for applications in mobile devices, wearables, and IoT devices.Another area of innovation in IC design is the use of advanced materials such as graphene and carbon nanotubes. These materials offer unique electrical and mechanical properties that can greatly enhance the performance of integrated circuits. For example, graphene-based transistors have demonstrated higher electron mobility and faster switching speeds compared to traditional silicon transistors, paving the way for next-generation computing devices with unprecedented speed and efficiency.In addition to new materials, machine learning and artificial intelligence (AI) are playing an increasingly important role in IC design. By leveraging AI algorithms, designers can automate the process of optimizing chip architectures, reducing time-to-market and improving overall performance. AI-driven design tools can analyze vast amounts of data to identify the most efficient circuit layouts and power management strategies, leading to more reliable and cost-effective ICs.Moreover, the integration of photonics into IC design is opening up new possibilities for high-speed data communication and processing. Photonic integrated circuits (PICs)use light instead of electricity to transmit and manipulate data, offering significant advantages in terms of bandwidth and latency. PICs are already being used in data centers and telecommunications networks to improve the performance and scalability of optical communication systems.Furthermore, the emergence of quantum computing represents a paradigm shift in IC design, with the potential to solve complex problems that are currently intractable for classical computers. Quantum ICs, which exploit the principles of quantum mechanics to perform calculations, have the potential to revolutionize fields such as cryptography, materials science, and drug discovery. While quantum computing is still in its infancy, ongoing research and development efforts are rapidly advancing the state-of-the-art, bringing us closer to realizing the full potential of this transformative technology.In conclusion, the field of IC design is experiencing rapid innovation driven by advancements in materials science, machine learning, photonics, and quantum computing. These technologies hold the promise of delivering faster, more efficient, and more powerful integrated circuits, with profound implications for a wide range of industries and applications. As we continue to push the boundaries of what is possible, the future of IC design looks brighter than ever before.。
5g的优点和缺点英文作文
5g的优点和缺点英文作文The Pros and Cons of 5G TechnologyThe rapid advancements in technology have revolutionized the way we live our lives. One of the latest and most significant developments in the world of telecommunications is the emergence of 5G technology. 5G, or the fifth generation of wireless communication systems, promises to deliver unprecedented speeds, lower latency, and a more efficient network infrastructure. While the potential benefits of 5G are undeniable, it is crucial to also consider the potential drawbacks and challenges associated with its implementation.One of the primary advantages of 5G is its significantly faster data transmission speeds. Compared to its predecessors, 5G offers download and upload speeds that are up to 100 times faster. This enhanced speed can greatly improve the user experience in various applications, such as streaming high-definition videos, playing online games, and seamless file transfers. The increased bandwidth provided by 5G also allows for more devices to be connected simultaneously without compromising performance.Another key benefit of 5G is its reduced latency. Latency refers to the time it takes for data to be transmitted and received. With 5G, latency can be reduced to as little as a few milliseconds, which is a vast improvement over the higher latency experienced in previous generations of wireless technology. This low latency is particularly important for applications that require real-time responsiveness, such as autonomous vehicles, remote surgery, and industrial automation.Furthermore 5G's improved network efficiency can lead to significant energy savings. The advanced architecture of 5G networks allows for more efficient use of spectrum and resources, reducing the overall energy consumption of the network infrastructure. This improved energy efficiency can have positive environmental implications, as it contributes to a more sustainable and eco-friendly telecommunications landscape.However, the implementation of 5G technology is not without its challenges and potential drawbacks. One of the primary concerns is the potential impact on human health and the environment. There are ongoing debates and studies regarding the potential health risks associated with the higher frequency electromagnetic radiation used in 5G networks. While the scientific consensus on the long-term effects is still inconclusive, the perceived risks have led to public apprehension and resistance in some regions.Additionally the deployment of 5G infrastructure can be a complex and costly undertaking. The installation of new cell towers and the upgrading of existing infrastructure require significant financial investment from telecommunication companies and governments. This can lead to higher costs for consumers and potentially widen the digital divide in regions where the investment in 5G infrastructure may be limited.Another potential drawback of 5G is the increased cybersecurity risks. The greater connectivity and data transmission capabilities of 5G networks can also make them more vulnerable to cyber threats such as hacking, data breaches, and network disruptions. Ensuring the security and privacy of 5G networks is crucial to mitigate these risks and maintain the trust of users.Moreover the transition to 5G may also have unintended consequences on certain industries and workforce. The increased automation and efficiency brought by 5G could lead to job displacements in sectors such as transportation and logistics. Policymakers and stakeholders will need to address these potential societal impacts and develop strategies to support affected communities and workers.In conclusion the potential benefits of 5G technology are indeedsignificant offering faster speeds lower latency and improved energy efficiency However the implementation of 5G also presents challenges and potential drawbacks that need to be carefully considered and addressed These include concerns about health and environmental impacts the high costs of deployment cybersecurity risks and the potential disruption to certain industries and workforce As we embrace the 5G revolution it is crucial that we develop a balanced and well-rounded understanding of its pros and cons to ensure its sustainable and responsible deployment for the betterment of society。
华为固定转换解决方案——PSTN更新简易解决方案说明书
Huawei Fixed Transformation Solution— The simple solution for PSTN renewalTrademark Notice, HUAWEI , and are trademarks or registered trademarks of Huawei Technologies Co.,Other trademarks, product, service and company names mentioned are the property of their respective owners.HUAWEI TECHNOLOGIES CO., LTD.Copyright © Huawei Technologies Co., Ltd. 2011. All rights reserved.No part of this document may be reproduced or transmitted in any form or by any means without prior written consent of Huawei Technologies Co., Ltd.General DisclaimerThe information in this document may contain predictive statements including, without limitation, statements regarding the future financial and operating results, future product portfolio, new technology, etc. There are a number of factors that could cause actual results and developments to differ materially from those expressed or implied in the predictive statements. Therefore, such information is provided for reference purpose only and constitutes neither an offer nor an acceptance. Huawei may change the information at any time without notice.HUAWEI TECHNOLOGIES CO., LTD.Huawei Industrial BaseBantian LonggangShenzhen 518129, P .R. ChinaTel: +86-755-28780808Version No.: M3-310290499-20120106-C-1.0Smooth network migrationHuawei fixed transformation solution simplifies the PSTN renewal.With the continued development of the telecom industry, most operators are still struggling with a declining ARPU, high churn rate of subscribers, high CAPEX/OPEX, and a relatively poor return on investment (ROI).Their common challenges can be summarized as follows:y Deal with the declining growth in PSTN voice revenue. y Optimize investment strategies to reduce the TCO of theirnetworks.y Launch innovative services to attract and retain customersto compensate for the declining revenue growth from traditional services.The PSTN Renewal Solution provides a comprehensive way to migrate legacy TDM networks to a fully IP-based network architecture in a smooth manner.One unified IMS based core network is capable of connecting all different kinds of access networks likeHuawei has developed the fixed transformation Solution to help operators meet these challenges. The Huawei fixed transformation Solution is a proven solution to help operators migrate their network smoothly, simplify the network architecture, and reduce operation and maintenance costs. At the same time, it brings together support for multimedia and convergence on a single core network. Many innovative services can be provided based on this platform to give a better end user experience and improve customer loyalty. These services will also become new sources of revenue, which will create a promising ROI. In a word, operators are able to cap their TDM investments and move forward towards an era of fully converged services.Other 11.56%No Invest 23.81%SS 10.2%PSTN Migration ChoicesData from 147 Operator’s selection in IMSWorld Forum 2011xPON,xDSL,LAN,WiMAX,CMTS for VoBB users, AGCF for legacy PSTN users(POTS/V5 etc) and MGCF or SIP GW for TDM PBX access, SBC/P-CSCF for IP PBX access.SmartCutover: Dedicated high-efficiency PSTN renewal tool.With more than 10 years of experience in PSTN migration and with a deep understanding of the concerns of operators in recent years, Huawei has developed a dedicated tool to overcome the common issues and key obstacles with PSTN network transformation. Considering the full scope of PSTN migration, SmartCutover includes the following four sub-tools:y Legacy PSTN analysis tool: Based on the resolved original data on legacy PSTN switches, all the essential information required for migration like networking, services, interconnection parameter, and so on can be extracted and reorganized as a unified format to support further network design, planning, requirement surveys, data conversion and network consultation.The analysis tool supports PSTN switches from all mainstream vendors. A highly scalable and open architecture is used to support new types of switches and new services by simply adding additional components. y Data conversion tool: The conversion tool is used to convert basic user data in the legacy PSTN switch to the MML command used for the Huawei IMS solution. Basic user data includes the user number, user authority, user attribute, user status, and so on. The conversion tool can efficiently perform a precise, rapid and integrated user data migration.y C4 cutover tool: Based on features like multiple signaling point, the C4 cutover tool helps connect peer equipment using the same signaling point code (SPC) as the target C4 switches. Compared to the traditional method, this tool can greatly shorten the cutoverWith the purpose of achieving full service inheritance during the migration, the following two options are available to maintain the consistency of legacy services at the access side: AGCF + H.248 MSAN and SIP-MSAN + P-CSCF. Neither of them is applicable for every operator. Which option should be used depends on the existing network situation and the specific deployment scenario. So a flexible, software-driven core network is required to support both choices and even to enable the operators to transit from one to the other. The Huawei fixed transformation solution supports both solutions on a single IMS core. Common TAS which provides basic services and supplementary services and IM-SSF together with legacy SCP which provides the traditional intelligent services like ring-back tones will support the service inheritance from the service layer.In order to make the new system work smoothly with the existing system like other core network elements and BSS/ OSS system, the system integration capability is also very important challenge. Huawei provides comprehensive IOT capability like signaling adaptation, service flow configuration based on different scenarios, SIP filter etc which can greatly improve the IOT efficiency and make the whole IOT process easier.Huawei has built 3 IOT labs worldwide to provide a timely support for global requirements. The integration with other mainstream vendor’s core network elements and integration with most of the mainstream OSS/BSS vendors has been done commercially all over the world which of course can guarantee a fast, safe and cost effective network and service delivery.At the upper layer of the IMS deployed in the fixed transformation solution, many enhanced services can be easily deployed to expand your business beyond voice services:Rich user experiencey Rich communication suite features provide addressbook synchronization, enhanced messaging, presence/group information, media sharing, and enriched calling to enhance the end-user experience. The Huawei RCS soft client can run on smartphones, tablets, dongles, PCs, STBs, and home GWs on various OS platforms, such as iOS, A ndroid, Blackberry, webOS, and so on. Huawei RCS provides a single number with fixed phone based continuity and interoperability, which can offer an enhanced user experience with full support forlegacy services. The E2E QoS guarantee with advanced features, such as HD voice and native interoperability with telephone networks are unique features of Huawei RCS."let the fixed phone go out" is the key benefit RCS provides to traditional fixed and full service operators. It can greatly help operators retain users and can create new revenue by extending the fixed market to mobile users.Huawei RCS soft client can be embedded into smartphones to greatly enhance the user experience.Unified address book and dial panel to support both CScall, SMS, IM, file transfer, and sharing.Social networking integration with support for most popular social networking applications, such as Facebook, Twitter, Flickr, and so on.y Convergent conference provides an open environmentfor any kind of access and devices to join in a single video conference, not only attendees in dedicated conferencing rooms, but also telecommuters with soft clients and mobile phone users. Plain voice, HD video, data, web, and telepresence can all access the same conference. In addition, interconnection with traditional H.323/Cisco conference systems can be supported and lower bandwidth is required for video conferencing compared to industry benchmarks. A unified web portal is used for flexible conference management.Huawei convergent conference provides flexible business models for different operators, such as hotel mode, resell, enterprise rental, and secondary operation, to increase revenue thanks to the generation of different CDR formats.y Convergent IP Centrex and business trunking is one ofthe services of Huawei IMS that best addresses the needs of business users. It gathers fixed lines, PBX (TDM or IP based), mobile phones, and soft phones into one group. Open interfaces (APIs) are also provided to connect third-party ICT applications, such as corporate IT applications,with rich features, such as voicemail-to-email, click-to-dial, etc.Huawei convergent IP Centrex application is built into the telecom application service (ATS9900), which means that operators that have already invested in Huawei IMS voice do not have to re-invest in any hardware or network adjustment for Centrex service, only additional licenses are required.The Huawei business trunking solution can support the legacy TDM PBX while simultaneously supporting IP PBX. There are three TDM PBX access options: SIP gateway when no TDM transmission resources are available, AGCF, and MGCF when TDM transmission resources are available. Based on Huawei flexible solution, integrated business mode with broadband rent and voice trunking rent can be easily accomplished.Future proof architectureWith the development of LTE, voice over LTE will become more and more important. The Huawei fixed transformation solution is ready to support VoLTE user access smoothly with only a software upgrade. The whole IMS core can be reused along with the common TAS to achieve service consistency on fixed and mobile networks.ICS is an efficient architecture that provides a single core control for different kinds of access networks (PSTN, xDSL, FTTx, and Mobile) and unified application servers that deliver a consistent and seamless user experience anywhere on anydevice. The Huawei fixed transformation solution can be upgraded to support ICS and provide full FMC services.All IMS core components are based on the ATCA platform, a high performance, reusable and scalable hardware platform. This leads to fewer network nodes, fewer spare parts, less energy consumption and a smaller footprint per user. At the same time, all components share the same O&M system. As a result, the TCO, especially OPEX, can be reduced significantly year over year.1- PSTN Renewal and FMC services 2- VoLTE access 3- Full ICS architectureSummaryPSTN transformation is a challenging task for operators. The Huawei IMS-based fixed transformation solution provides an optimal way to make this process faster, easier and safer. The solution supports full legacy PSTN access and complete service inheritance. In addition to voice service, other servicescan easily be provisioned and integrated to increase ARPU. Based on the standard ATCA platform, a highly re-usable unified network architecture can be achieved smoothly in a cost effective way. Huawei IMS-based fixed transformation solution is the right choice to simplify your PSTN renewal.。
天地一体化信息网络总体架构设想
天地一体化信息网络总体架构设想一、本文概述Overview of this article随着信息技术的飞速发展，信息网络已经成为现代社会不可或缺的基础设施。
然而，传统的地面信息网络面临着诸多挑战，如覆盖不全、容量瓶颈、安全性问题等。
为了应对这些挑战，天地一体化信息网络的概念应运而生。
本文旨在探讨天地一体化信息网络的总体架构设想，分析其潜在的优势与挑战，并提出相应的解决策略。
With the rapid development of information technology, information networks have become an indispensable infrastructure in modern society. However, traditional ground information networks face many challenges, such as incomplete coverage, capacity bottlenecks, and security issues. In order to address these challenges, the concept of integrated information networks between heaven and earth has emerged. This article aims to explore the overall architecture of the integrated information network between heaven and earth, analyze its potential advantages and challenges, and proposecorresponding solutions.天地一体化信息网络是一种将地面网络与空间网络深度融合的新型网络架构，旨在实现全球范围内的无缝覆盖和高效通信。
Allied Telesis AT-DC2552XS 数据中心交换机说明说明书
Switchesproduct informationDesigned for virtualized data center and cloud environments, the Allied Telesis AT-DC2552XS switch provides high density 10GbE and 40GbE connectivity, making it ideal for today’s mini and small data centers, which use up to hundreds of server ports.The Allied Telesis AT-DC2552XS is a 48 x 10GbE (SFP+) port high-bandwidth and high-density switch designed for data center applications. It also provides four QSFP+ 40GbE slots for “fat-pipe” high bandwidth uplinks. This switch delivers 1280Gbps of switching fabric with ultra low sub-μsec latency. Airflow has been optimized for front-to-back cooling for data center environments. The unit can also accommodate a 1+1 resilient power supply, along with these specifications, in a very compact 1RU unit chassis.A smarter data center can be achieved by connecting servers and storage facilities with a high-speed and low latency network fabric that is faster, greener, open, and easy to manage.Advanced Energy Efficiency Energy efficient architecture and front-to-back air-flow cooling of the AT-DC2552XS are critical factors in optimizing data center economics—as companies must balance performance with power consumption to meet energy budgets.High-bandwidthAs bandwidth-intensive applications—such as Web 2.0, virtualization, High-Performance Computing (HPC) and Network Attached Storage (NAS)—continue to proliferate within enterprise data centers, 10 Gigabit Ethernet (10GbE) provides a cost-effective way to increase throughput and seamlessly deliver customer Service Level Agreements.Future Proofing10GbE empowers companies toexpand application capabilities, reduce time to solve complex financial and scientific applications, and quickly respond to changing customer needs and market conditions.In combination with the AT-VNC10S Network Interface Cards for servers, it helps clients to reduce the use of I/O adapters, reducing costs and complexity.High AvailabilityThe AT-DC2552XS has two slots for hot-swappable PSUs (Power Supply Unit) and fans. In addition, SFP+ and QSFP modules can be easily removed and replaced with no interruption to the network. These hot-swappable modules guarantee the continued delivery of essential services.Cut-throughCut-through switching sends packets to their destination as soon as the first part is ready. The delay is minimal and the packet reaches its destination in the shortest possible time. With cut-through mode, the AT-DC2552XS forwards packets with a latency of 505 nanoseconds with 40Gb / 800 nanoseconds with 10Gb and is ideal for inter-server communication.Air FlowCooling air flow has become a major design concern in modern data centers. The AT-DC2552XS utilizes front (PSU and fan side) to back (ports side) airflow, which is suitable for rack mounting in data centers.Eco-friendlyIn keeping with our commitment to environmentallyfriendly products, this switch is designedto reduce power consumption and minimize hazardous waste.alliedtelesis .comAT-DC2552XSHigH PErFormAnCE, Low LAtEnCy toP-oF-rACk DAtA CEntEr SwitCHResilient Ethernet Fabric (REF)1 increases availability using a dedicated bypass link. If one of the links or units fails, the bypass link restores connectivity. By setting up the same LACP trunk group over two AT-DC2552XS units, REF uses link aggregation to increase throughput beyond what a single connection could sustain, while providing link path redundancy.»Master-less»Layer 2 mesh on spine-leaf model»Active-active, multi-path»Easy setup Master-less»There is no “synchronize” process which the hardware stacking feature usually requires. Instead of setting up “masters” and “members,” REF recognizes the other device just as a partner and eliminates the downtime of master fail-over.Layer 2 Mesh on Spine-Leaf»One pair of AT-DC2552XS switches with aggregationmode supports up to five pair of AT-DC2552XS withToR mode, which would connect a maximum of 40servers per rack.Active-Active, Multi-Path»While Spanning Tree Protocol requires active-standbyconfiguration and switchover time for failure, REFsupports active-active configuration, preventing anyperceptible disruption in the case of a link failure.Even if one of the devices fails, an alternative pathis secured and ensures absolute minimal networkdowntime.Easy Setup»REF is configured with QSFP modules between twoAT-DC2552XS units, and breakout cables betweenthe ToR and the aggregation switch. Resilient Ethernet Fabric1Requires updating to controlled introduction software version 2.5.3.1.Contact your local Allied Telesis support staff for details.2 | AT-DC2552XSAT-DC2552XS | 31 - 4049, 53 (40G), 57- 64 (10G)Ports for Aggregation49 - 56 (10G Up to 10 breakout cables per aggregation switch4 | AT-DC2552XSSpecificationsPort»Switch port SFP+ slot x 48 ports QSFP+ slot x 4 »Console port RS-232 (USB connector) x 1 »Management port 10/100/1000T (RJ-45 connector) x 1 Auto negotiation, MDI-MDI-XSystem»Forwarding rate 952.38Mpps »Switching capacity 1280Gbps »128K MAC addresses »Cut-through mode Latency 40GB:505 ns (64 byte) 10GB:800 ns (64 byte) »2GB RAM»128MB flash memory »1.3Ghz CPU»9MB packet buffer»Maximum jumbo frames 12Kbytes»32 link aggregation group / eight members per groupWirespeed Switching on all Ethernet ports»14,880,000pps for 10Gbps Ethernet »59,523,800pps for 40Gbps EthernetEnvironmental Specifications»Operating temperature 0ºC to 40ºC »Storage temperature -20ºC to 60ºC »Operating humidity 10% to 80% (non-condensing) »Storage humidity 5% to 90% (non-condensing)Port Configuration»Auto-negotiation, duplex, MDI/MDI-X, IEEE 802.3x flow control »Packet storm protection »Port mirroring»Broadcast storm control »Ethernet statistics »Egress-rate-limit »LinkTrapEthernet Specifications»IEEE 802.3 10T* »IEEE 802.3u 100TX* »IEEE 802.3ab 1000T*»IEEE 802.3ae 10G-SR, 10G-LR»IEEE 802.3ba 10G-SR4/XLPPI,40G-CR4 »IEEE 802.1Q Virtual LANs»IEEE 802.3ad (LACP) Link aggregation »IEEE 802.3z Gigabit Ethernet 2* Only for management port useQuality of Service (QoS)»Head-of-line blocking prevention »Eight egress queues per port»IEEE 802.1p Class of Service with strict and weighted round robin scheduling/strict priority scheduling »Access Control Lists (ACLs) »Policy-based QoS 2Spanning Tree Protocol»IEEE 802.1D Spanning Tree Protocol »IEEE 802.1w Rapid Spanning Tree »IEEE 802.1s Multiple Spanning Tree2 Requires updating to controlled introduction software version 2.5.4.1. 3Requires updating to controlled introduction software version 2.5.3.1. Contact your local Allied Telesis support staff for details.Management»Enviromental monitoring»DHCP client»RFC 1350 TFTP client»NTP»Zmodem»HTTP»TFTP»RFC 1157 SNMPv1»RFC 1901 SNMPv2c»RFC 2571-5 SNMPv3»RFC 1757 RMON group 1, 3, 9»Syslog client support»Event log»Telnet»SSHv2MIB Support»RFC 1643 Ethernet-like MIB»Allied Telesis private MIB»RFC 1757 RMON MIB»RFC 1493 Bridge MIB»RFC 1573/2863 Interfaces group MIB »RFC 1213 MIB-II»RFC 1215 TRAP MIB»RFC 3635 Ethernet MIBVLAN»4094 VLANs»MAC based VLANs – 1K»Port-based VLANs»IEEE 802.1Q tag-based VLANs»Double tag VLAN (Q-in-Q)4Link Aggregation»Static trunking»IEEE 802.3ad LACP»IP option»Dynamic LACP»Port trunkingIP Multicasting»RFC 1112 IGMPv1 snooping»RFC 2236 IGMPv2 snooping»RFC 3376 IGMPv3 snooping»Multicast groups - 255Security»Hardware packet filtering»Layer 2/3/4 Access Control Lists (ACLs)»512 ACL profiles»256 rules per ACL profile»ACLs based on:- ICMP- IP- MAC address- IP protocol- TCP- UDP»DoS attack protection- Smurf- SYN flood- Teardrop- Land- IP option- Ping attackCompliance Standards»IEEE 802.3ae, 10G SFP+ - SFP+ fiber, SFP+ directattach»IEEE 802.3ba - QSFP+Safety and Electromagnetic EmissionsCertifications»EMI: FCC class A, CISPR class A, EN55022 class A»C-TICK, VCCI Class A, CE»Immunity: EN50024, EN601000-3-3,EN601000-3-2»Safety: UL 60950-1 (cUlus), EN60950-1 (TUV)Physical SpecificationsCompliant with European RoHS standardsPackage Specifications»AT-DC2552XX switch with two PSU bay covers andtwo FAN unit bay covers»Management cable (RS-232 to USB)»Rubber feet and 19 in rack-mountable hardware kitaccessories»Install guide and CLI users guide available at/supportPhysical SpecificationsDimensions 44.1 cm x 46 cm x 4.4 cm(W x D x H) 17.4 in x 18.1 in x 1.7 inWeight 8.3 kg /18.3 lb (chassis only)11.3 kg/24.9 lb (chassis withtwo fans and two PSUs)Power Characteristics»Voltage: 100-240V AC (10% auto-ranging)»Frequency: 50/60 Hz»Maximum current: 14A @ 100V»Heat dissipation: 900 BTU/hrPower Consumption»250W (max 280W)4Requires updating to controlled introduction software version 2.5.3.1.Contact your local Allied Telesis support staff for details.AT-DC2552XS | 5Ordering InformationAT-DC2552XS 48-port SFP+ slot4-port QSFP slot 1-port console port 1-port management port 2 slots for PSUs 2 slots for fans AT-PWR06-xxHot-swappable AC power supplyAT-FAN06Hot-swappable fan(Two fans are needed to operate. Reverse cooling airflow — port side to PSU/fan side — is not supported)Where xx =10 for US power cord 30 for UK power cord40 for Australian power cord 50 for European power cordQSFP+ and CableAT-QSFP1CUQSFP+copper cable 1 m AT-QSFP3CUQSFP+ copper cable 3 m AT-QSFPSR QSFP+ moduleOptical CablesAT-MTP12-1MTP cable for AT-QSFPSR, 1 m AT-MTP12-5MTP cable for AT-QSFPSR, 5 mBreakout Cables 5AT-QSFP-4SFP10G-3CUQSFP to 4 x SFP+ breakout direct attach cable (3 m)AT-QSFP-4SFP10G-5CUQSFP to 4 x SFP+ breakout direct attach cable (5 m)SFP+ ModulesAT-SP10SR 10G-SR AT-SP10LR 10G-LRAT-SP10TW110G SFP+ direct attach cable (1 m)AT-SP10TW310G SFP+ direct attach cable (3 m)AT-SP10TW710G SFP+ direct attach cable (7 m)SFP Modules 6AT-SPLX10 1000LX AT-SPSX 1000SX5Requires updating to controlled introduction software version 2.5.3.1. Contact your local Allied Telesis support staff for details.6Requires updating to controlled introduction software version 2.5.4.1. Contact your local Allied Telesis support staff for details.alliedtelesis .com© 2013 Allied Telesis, Inc. All rights reserved. Information in this document is subject to change without notice. All company names, logos, and product designs that are trademarks or registered trademarks are the property of their respective owners.617-00453 Rev. ENorth America Headquarters | 19800 North Creek Parkway | Suite 100 | Bothell | WA 98011 | USA | T: +1 800 424 4284 | F: +1 425 481 3895Asia-Pacific Headquarters | 11 Tai Seng Link | Singapore | 534182 | T: +65 6383 3832 | F: +65 6383 3830EMEA & CSA Operations | Incheonweg 7 | 1437 EK Rozenburg | The Netherlands | T: +31 20 7950020 | F: +31 20 7950021。
英语作文-集成电路设计行业中的人工智能与机器学习应用
英语作文-集成电路设计行业中的人工智能与机器学习应用The application of artificial intelligence and machine learning in the integrated circuit design industry has brought about significant advancements and improvements. With the rapid development of technology, the demand for more efficient and intelligent design solutions has become increasingly important. In this article, we will explore the various ways in which artificial intelligence and machine learning are being applied in the integrated circuit design industry.One of the key areas where artificial intelligence and machine learning are making a significant impact is in the optimization of the design process. Traditionally, the design of integrated circuits has been a complex and time-consuming task, requiring a great deal of manual effort and expertise. However, with the advent of artificial intelligence and machine learning, designers are now able to leverage advanced algorithms and models to automate and optimize many aspects of the design process. This has led to significant improvements in design efficiency, as well as the ability to explore and evaluate a much larger design space than was previously possible.Another important application of artificial intelligence and machine learning in the integrated circuit design industry is in the area of design validation and testing. As the complexity of integrated circuits continues to increase, the task of validating and testing designs has become increasingly challenging. Artificial intelligence and machine learning techniques are now being used to develop advanced simulation and testing tools that are capable of identifying and addressing potential design issues much more quickly and accurately than traditional methods. This has not only improved the reliability and performance of integrated circuits, but has also helped to reduce the time and cost associated with the design validation process.Furthermore, artificial intelligence and machine learning are also being used to enhance the overall performance and power efficiency of integrated circuits. Byleveraging advanced algorithms and models, designers are now able to develop more sophisticated and intelligent circuit architectures that are capable of optimizing performance and power consumption in real-time. This has led to the development of more efficient and energy-conscious integrated circuit designs, which are crucial for meeting the demands of modern electronic devices.In addition to these applications, artificial intelligence and machine learning are also being used to improve the overall design process by enabling more intelligent and automated decision-making. Designers are now able to leverage advanced algorithms and models to analyze and interpret large volumes of design data, enabling them to make more informed decisions and develop more innovative and effective design solutions.In conclusion, the application of artificial intelligence and machine learning in the integrated circuit design industry has brought about significant advancements in design efficiency, validation and testing, performance and power efficiency, as well as overall decision-making. As technology continues to evolve, we can expect to see even more innovative and intelligent design solutions emerge, further pushing the boundaries of what is possible in the integrated circuit design industry.。
强大的基础设施和创新的支持英语雅思作文
Infrastructure Backbone and the Catalyst ofInnovationIn the dynamic landscape of modern society, the significance of robust infrastructure and innovativesupport cannot be overstated. These two pillars form the foundation of any thriving nation, driving economic growth, enhancing social welfare, and fostering a culture of continuous improvement and progress.Infrastructure is the backbone of any nation, providing the literal and figurative framework for development. It encompasses physical structures like roads, bridges, airports, and railways, which are critical for theefficient movement of people and goods. But infrastructure also extends to digital networks, including broadband internet, mobile connectivity, and data centers, which are now integral to the functioning of modern economies. Awell-developed infrastructure not only ensures无缝对接connectivity and accessibility but also acts as a catalyst for innovation, attracting talent, capital, and ideas.Innovation, on the other hand, is the lifeblood of any economy, driving competitive advantage and sustained growth.It encompasses technological advancements, business model reinventions, and social innovations that improve lives. However, innovation does not sprout spontaneously; it requires a nurturing environment that is supported by robust infrastructure. This support can range from physical spaces like incubators and accelerators to digital platforms that connect innovators with resources, markets, and each other.The relationship between infrastructure and innovation is symbiotic. On one hand, infrastructure creates the conditions for innovation to flourish. For instance, high-speed internet connectivity enables remote work, online learning, and digital entrepreneurship, all of which are engines of innovation. On the other hand, innovation can enhance and transform infrastructure. For example, advancements in renewable energy technology are driving the transition to greener, more sustainable infrastructure.The combined power of robust infrastructure and innovative support is transformative. It has the potential to lift entire communities out of poverty, create new industries and jobs, and address pressing global challengeslike climate change and social inequality. It is this combination that has propelled many nations to theforefront of global competitiveness, making them beacons of hope and prosperity in an increasingly interconnected world. In conclusion, robust infrastructure and innovative support are indispensable for building sustainable and inclusive societies. As we move into the future, it is crucial that we prioritize investments in both areas, ensuring that our infrastructure remains state-of-the-art and our innovation ecosystems thrive. By doing so, we can create a world that is not only more connected and accessible but also more equitable and prosperous.**基础设施的支柱与创新的催化剂**在现代社会快速发展的风景画中，强大的基础设施和创新的支持的重要性不言而喻。
应用技术学院-计算机专业英语复习资料
应用技术学院-计算机专业英语复习资料专业英语复习资料一、请写出以下单词的中文意思。
1、floppy disk软盘2、printer打印机3、optical disk光盘4、formatting toolbar 格式工具条5、formula方程式6、relational database关系数据库7、antivirus program抗病毒程序8、fragmented破碎9、user interface用户界面10、bus line总线11、smart card智能卡12、motherboard主板13、digital camera数码相机14、fax machine传真机15、ink-jet printer喷墨打印机16、access time访问时间17、direct access直接存取18、Bluetooth蓝牙19、digital signal数字签名20、protocols协议21、operating system 操作系统22．requirements analysis 需求分析23．network security 网络安全24．data structure 数据结构25．decision support system 决策支持系统26．software crisis 软件危机27．computer virus 电脑病毒28．email attachment 电邮附件29．central processing unit ( CPU )中央处理单元30．ink-jet printer 喷墨打印机31. multimedia 多媒体32. software life cycle软件生命周期33. structured programming 结构化程序34. functional testing 功能测试35. word processor 文字处理36. code windows 代码窗口37. firewall 防火墙38. LAN local area network局域网39. hacker 黑客40. switch 开关41．数据库管理系统database management system42．传输控制协议transmission control protocol43．多文档界面multiple document interface 44．面向对象编程Object-oriented programming 45．只读存储器read-only memory46．数字视频光盘Digital Video Disc47．计算机辅助设计computer aided design48．结构化查询语言Structured Query Language49．通用串行总线Universal Serial Bus50．企业之间的电子商务交易方式EDi二、单项选择题。
Bandwidth efficient source tracing (BEST) routing
专利名称：Bandwidth efficient source tracing (BEST)routing protocol for wireless networks发明人：Jose Joaquin Garcia-Luna-Aceves,Jyoti Raju申请号：US09883082申请日：20010615公开号：US07002949B2公开日：20060221专利内容由知识产权出版社提供专利附图：摘要：A bandwidth efficient routing protocol for wireless ad-hoc networks. This protocol can be used in ad-hoc networks because it considerably reduces controloverhead, thus increasing available bandwidth and conserving power at mobile stations. Italso gives very good results in terms of the throughput seen by the user. The protocol is a table-driven distance-vector routing protocol that uses the same constraints used in on-demand routing protocols, i.e., paths are used as long as they are valid and updates are only sent when a path becomes invalid. The paths used by neighbors are maintained and this allows the design of a distance-vector protocol with non-optimum routing and event-driven updates, resulting in reduced control overhead.申请人：Jose Joaquin Garcia-Luna-Aceves,Jyoti Raju地址：San Mateo CA US,Saratoga CA US国籍：US,US代理人：John P. O'Banion更多信息请下载全文后查看。
CommScope Optical LAN Solutions (OLS) 产品指南说明书
Passive Optical LAN guideCommScope’s Optical LAN Solutions (OLS) offer a complete end-to-end cabling solution to support passive optical LAN (POL). POL is the enterprise-level architecture adapted from the service provider passive optical network (PON) technology, which has been used to deliver bundled voice, data and video services to the premises for more than 20 years.Optical LAN solution overviewIn a POL architecture, the network consists of a core switch known as an optical line terminal (OLT) connected to an end device or optical network terminal (ONT) by up to 20 km (or more) of passive singlemode fiber-optic cabling. CommScope’s OLS includes products designed specifically to support this technology in a simple, efficient and cost-effective manner.Our OLS is highly intuitive and simple to design and deploy while remaining flexible enough to adapt to any network distribution challenge. All-plenum-rated construction along with preterminated plug-and-play connectivity streamline the design and installation process, eliminating the need for costly, time-consuming field terminations. Our patented Rapid Reel technology also significantly lowers the number of required parts and dramatically reduces deployment time. We also offer traditional field-termination capabilities where the use of preterminated cabling is not an option.ARCHITECTURE DESIGNMore so than traditional point-to-point networks, POL designs can vary greatly depending on network requirements, architecture, building layout and economics. CommScope’s OLS offers the designer an extensive portfolio to meet any unique distribution challenge. This brochure includes not only POL-specific products but a broad offering of more traditional fiber network connectivity components that work in conjunction with our OLS products to establish the most effective infrastructure for every application.Infrastructure support for passive optical LAN can be broken into two “foundation” topologies. These are hub and terminal distribution and distributed splitter distribution. Each of these “foundation” topologies can be modified to suit any application and can also be combined into hybrid topologies to meet specific network requirements.Figure 1: POL architectureOption 1: Hub and terminal·Most efficient for medium to large deployments·Optimal for next-generation optical LAN technology upgrades ·Flexible solution for high-bandwidth device (re)distribution ·Maximizes OLT port utilization ·Least floor space requiredOption 2: Distributed splitter ·Lowest CapEx ·Great scalability·Works well for smaller deployments ·Poor OLT port utilization·Comparable floor space to FDH/FDT ·Less cable than rack mount ·Easy to design and understand·Less efficient for large or complex deploymentsFigure 2: Hub and terminal architectureFigure 3: Distributed splitter architectureOrdering guide FIBER PANELSCommScope’s standard density (SD) fiber-optic panels are available in 1U, 2U and 4U sizes, with fixed or sliding trays, and accept LGX and ReadyPATCH®-style modules and adapter panels.In addition to standard structured cabling, these panels can accept preterminated SC/APC-MPO modules for preterminated installations, as well as SC/APC adapter panels for traditional field termination.Features:·Modular design utilizing LGX footprint offers pay-as-you-grow flexibility ·Robust offering of preterminated, field-terminated or splicing cassettes ·Scalable up to 12 SC fibers per module·Simplifies moves, adds and changesFigure 4: SD fiber panel Figure 5: SC/APC-MPO moduleRapid Fiber™ distribution hub (iFDH)CommScope’s Rapid Fiber distribution hub organizes and administersoptical fiber cables and passive optical splitters for enterprise opticalLAN applications. The enclosures support plug-and-play terminationwith a cross-connect/interconnect interface that makes installation,maintenance, and changes faster and easier. The Rapid Reel feedercable speeds installation time and conveniently stores slack inside theiFDH.Features:·Supports plug-and-play termination·Can be either wall or rack mounted with the hardware providedFigure 6: iFDH ·Traditional swing-frame design allows superior rear access·Includes Rapid Reel feeder cable·Designed to meet NEMA-12 requirements·UL 1863 ListedNotes:* Splitters are purchased separately; ordering information on the following page.** See next section for MPO-MPO cable assemblies*** LSZH options also available. Please contact CommScope for options.Mini plug-and-play splitter modulesCommScope’s mini plug-and-play splitter modules support centralized splitting architectures. The modules are available in a wide range of split ratios. The rugged packaging is built for high performance, while the true plug-and-play design reduces installation time.Features:·Bend-optimized fiber and ruggedized extreme temperature cabling ·Operating temperature range -55°C to +85°C ·Wavelength range of 1260–1635 nm·Easy to insert and remove without affecting adjacent splitters ·UL 1863 listedFigure 7: Plug-and-play splitterFigure 8: Rack-mount splitterRapid Fiber distribution terminalCommScope’s Rapid Fiber distribution terminal (FDT) provides a compact, NEMA-12 rated solution for connecting optical fiber cables within enterprise environments and serves as a distribution/ consolidation point. It eliminates the need for splice cases and separate cable assemblies by integrating the Rapid Reel cable payout system. The use of factory-terminated and -tested MPO connectors instead of splicing provides a plug-and-play environment that reduces labor costs and speeds project completion. The Rapid FDT provides a lockable consolidation point and localized patch field, allowing for precise cable length customization in the field while reducing overall cable volume and simplifying routing from the FDH to the user area. The Rapid FDT’s compact footprint enables it to be placed under raised floors, above ceilings, or wall mounted.Features:·Built-in Rapid Reel technology allows for easy payoff of MPO stub ·Patented breakaway spool flanges reduce slack storage size to within the enclosure’s footprint·Utilizes reduced bend radius fiber·UL 1863 listedFigure 9: Rapid Fiber distribution terminalFigure 10: Mini RDT*Note: Other cable lengths available. Please contact CommScope for additional options.Fiber splitter boxesCommScope’s fiber splitter boxes (FSB) are mini fiber distribution hubs that can be used for plug-and-play (PNP) or fusion splice applications.When used as a plug-and-play box, they are ideal for uses such as lower count floors or buildings, extra capacity requirements beyond the standard fiber distribution hub (FDH), and when localized splitting or physical path redundancy (using a 2x32 split) is desired.The same box can also be used to extend services beyond the primary building to other smaller buildings with limited users on the campus. In this type of application, the FSB is typically spliced to the OSP fiber cable connecting the buildings and would offer the optical splitting required to provide PON services to the second building.These wall boxes provide a small footprint for splitting, terminating, and splicing. FSBs accept standard plug-and-play splitters and can be easily added after the wall box has been installed. FSBs accommodate 1x8, 1x16, 1x32, 2x16 and 2x32 splitters. Wall mounting provides significant space savings and the unique swing frame design allows foreasy access to the back section of the wall box.Figure 11: FSB indoor enclosureFeatures & Benefits:·Dual hinge design creates separation between rear splitter section and front patching access ·Splitters can be easily installed after wall box installation, allowing for separate purchase ·Provides up to 32 customer access ports per splitter·Dual hinge provides small footprint on the wall while maintaining excellent hand access to connectors ·Accepts standard mini-PNP splitter modules (same as iFDH) ·UL 1863 listedOptical fiber cablesThe reduced bend radius singlemode cable assemblies are used to connect the user area to the Rapid FDT or when connecting the ONT to the wall plate at the user end of the optical LAN.CommScope’s singlemode reduced bend radius cable assemblies have a bend radius of 7.5 mm and are backwards compatible with standard singlemode fiber. CommScope offers ultra physical contact (UPC) or angled physical contact (APC) SC connector styles. These assemblies maintain tight tolerances regarding the geometry and concentricity of the ferrule to maintain low insertion loss values. All cable assemblies undergo stringent testing for both insertion loss and return loss at thefactory before shipment, ensuring high quality.Figure 12: SC connectorsFigure 13: Simplex drop cablesFigure 14: MPO trunk cableSIMPLEX DROP CABLES (3 MM DIAMETER)SINGLEMODE REDUCED BEND RADIUS MULTIFIBER CABLE ASSEMBLIESyyy = length in metersAdditional options are available; contact CommScope for assistance.Easy access zone enclosures and Hideout outletsHideout features:·Double-gang box with single-gang cover recommended. ·May not fit all single-gang boxes. ·Hides and protects cable connections.·Feeds from bottom to allow flush furniture placement. ·Fits standard electrical boxes.·Each kit includes sub-plate, faceplate, adhesive labels, cable ties, and mounting screws. ·Media modules and icons must be ordered separately. Faceplates are plastic except for the stainless steel version. ·Accepts the following (see table for detailed load information): – Shielded or unshielded SL Series jacks – Simplex or duplex fiber-optic adapters – SL Series inserts ·Shielded SL Series jacks work in bottom row of faceplate only.Easy access zone enclosure features:·Economical with very low profile·Supports a single adapter plate or MPO cassette ·Gasketed entry to reduce dust intrusion ·Separate mounting/strain relief plate ·Not plenum rated ·Captive fasteners ·Can be magnet mounted ·Robust construction ·Internal bonding lug·Nominal dimensions:1.75 in (4.5 cm) H x 11 in (28 cm) D x 5.4 in (14 cm) WFigure 16: Easy access zone enclosureFigure 15: Hideout wall boxSnap-on coverScrew-on cover11 Passive Optical LAN GuideAngled faceplates & SC APC simplex adapterFeatures:·Accepts simplex and duplex fiber connectors·Accepts all AMP-TWIST jacks, SL Series jacks, and SL Series inserts ·Angled connector exits ·Protects connections·Allows closer furniture placementFigure 17: Angled faceplatesFigure 18: SC APC simplex adapterNote: Additional fiber adapters and copper outlets available. Please contact CommScope for detailed product information.CommScope (NASDAQ: COMM) helps design, buildand manage wired and wireless networksaround the world. As a communications infrastructureleader, we shape the always-on networks oftomorrow. For more than 40 years, our globalteam of greater than 20,000 employees, innovatorsand technologists has empowered customers in allregions of the world to anticipate what’s nextand push the boundaries of what’s possible.Discover more at Visit our website or contact your local CommScope representative for more information.© 2017 CommScope, Inc. All rights reserved.All trademarks identified by ® or ™ are registered trademarks or trademarks, respectively, of CommScope, Inc. This document is for planning purposes only and is not intended to modify or supplement any specifications or warranties relating to CommScope products or services. CommScope is committed to the highest standards, of business integrity and environmental sustainability with a number of CommScope’s facilities across the globe certified in accordance with international standards including ISO 9001, TL 9000, and ISO 14001.Further information regarding CommScope’s commitment can be found at /About-Us/Corporate-Responsibility-and-Sustainability.CO-112425.1-EN (01/18)。
NVIDIA Volta架构下CUDA应用调优指南说明书
Application NoteTable of Contents Chapter 1. Volta Tuning Guide (1)1.1. NVIDIA Volta Compute Architecture (1)1.2. CUDA Best Practices (1)1.3. Application Compatibility (2)1.4. Volta Tuning (2)1.4.1. Streaming Multiprocessor (2)1.4.1.1. Instruction Scheduling (2)1.4.1.2. Independent Thread Scheduling (2)1.4.1.3. Occupancy (3)1.4.1.4. Integer Arithmetic (3)1.4.2. Tensor Core Operations (3)1.4.3. Memory Throughput (4)1.4.3.1. High Bandwidth Memory (4)1.4.3.2. Unified Shared Memory/L1/Texture Cache (4)1.4.4. Cooperative Groups (4)1.4.5. Multi-Process Service (5)1.4.6. NVLink Interconnect (5)Appendix A. Revision History (6)Chapter 1.Volta Tuning Guide1.1. NVIDIA Volta Compute Architecture Volta is NVIDIA's latest architecture for CUDA compute applications. Volta retains and extendsthe same CUDA programming model provided by previous NVIDIA architectures such as Maxwell and Pascal, and applications that follow the best practices for those architectures should typically see speedups on the Volta architecture without any code changes. This guide summarizes the ways that an application can be fine-tuned to gain additional speedups by leveraging Volta architectural features.1Volta architecture comprises a single variant: GV100. A detailed overview of the major improvements in GV100 over earlier NVIDIA architectures is provided in a white paper entitled NVIDIA Tesla V100 GPU Architecture: The World's Most Advanced Datacenter GPU.For further details on the programming features discussed in this guide, please refer to the CUDA C++ Programming Guide.1.2. CUDA Best PracticesThe performance guidelines and best practices described in the CUDA C++ Programming Guide and the CUDA C++ Best Practices Guide apply to all CUDA-capable GPU architectures. Programmers must primarily focus on following those recommendations to achieve the best performance.The high-priority recommendations from those guides are as follows:‣Find ways to parallelize sequential code,‣Minimize data transfers between the host and the device,‣Adjust kernel launch configuration to maximize device utilization,‣Ensure global memory accesses are coalesced,‣Minimize redundant accesses to global memory whenever possible,1Throughout this guide, Kepler refers to devices of compute capability 3.x, Maxwell refers to devices of compute capability 5.x, Pascal refers to device of compute capability 6.x, and Volta refers to devices of compute capability 7.x.‣Avoid long sequences of diverged execution by threads within the same warp.1.3. Application CompatibilityBefore addressing specific performance tuning issues covered in this guide, refer to the Volta Compatibility Guide for CUDA Applications to ensure that your application is compiled in a way that is compatible with Volta.1.4. Volta Tuning1.4.1. Streaming MultiprocessorThe Volta Streaming Multiprocessor (SM) provides the following improvements over Pascal. 1.4.1.1. Instruction SchedulingEach Volta SM includes 4 warp-scheduler units. Each scheduler handles a static set of warps and issues to a dedicated set of arithmetic instruction units. Instructions are performed over two cycles, and the schedulers can issue independent instructions every cycle. Dependent instruction issue latency for core FMA math operations are reduced to four clock cycles, compared to six cycles on Pascal. As a result, execution latencies of core math operations can be hidden by as few as 4 warps per SM, assuming 4-way instruction-level parallelism ILP per warp. Many more warps are, of course, recommended to cover the much greater latency of memory transactions and control-flow operations.Similar to GP100, the GV100 SM provides 64 FP32 cores and 32 FP64 cores. The GV100 SM additionally includes 64 INT32 cores and 8 mixed-precision Tensor Cores. GV100 provides up to 84 SMs.1.4.1.2. Independent Thread SchedulingThe Volta architecture introduces Independent Thread Scheduling among threads in a warp. This feature enables intra-warp synchronization patterns previously unavailable and simplifies code changes when porting CPU code. However, Independent Thread Scheduling can also lead to a rather different set of threads participating in the executed code than intended if the developer made assumptions about warp-synchronicity2 of previous hardware architectures. When porting existing codes to Volta, the following three code patterns need careful attention. For more details see the CUDA C++ Programming Guide.‣To avoid data corruption, applications using warp intrinsics (__shfl*, __any, __all, and __ballot) should transition to the new, safe, synchronizing counterparts, with the *_sync suffix. The new warp intrinsics take in a mask of threads that explicitly define which lanes (threads of a warp) must participate in the warp intrinsic.2The term warp-synchronous refers to code that implicitly assumes threads in the same warp are synchronized at every instruction.‣Applications that assume reads and writes are implicitly visible to other threads in the same warp need to insert the new __syncwarp() warp-wide barrier synchronizationinstruction between steps where data is exchanged between threads via global or shared memory. Assumptions that code is executed in lockstep or that reads/writes from separate threads are visible across a warp without synchronization are invalid.‣Applications using __syncthreads() or the PTX bar.sync (and their derivatives) in such a way that a barrier will not be reached by some non-exited thread in the thread block must be modified to ensure that all non-exited threads reach the barrier.The racecheck and synccheck tools provided by cuda-memcheck can aid in locating violations of points 2 and 3.1.4.1.3. OccupancyThe maximum number of concurrent warps per SM remains the same as in Pascal (i.e., 64), and other factors influencing warp occupancy remain similar as well:‣The register file size is 64k 32-bit registers per SM.‣The maximum registers per thread is 255.‣The maximum number of thread blocks per SM is 32.‣Shared memory capacity per SM is 96KB, similar to GP104, and a 50% increase compared to GP100.Overall, developers can expect similar occupancy as on Pascal without changes to their application.1.4.1.4. Integer ArithmeticUnlike Pascal GPUs, the GV100 SM includes dedicated FP32 and INT32 cores. This enables simultaneous execution of FP32 and INT32 operations. Applications can now interleave pointer arithmetic with floating-point computations. For example, each iteration of a pipelined loop could update addresses and load data for the next iteration while simultaneously processing the current iteration at full FP32 throughput.1.4.2. Tensor Core OperationsEach Tensor Core performs the following operation: D = AxB + C, where A, B, C, and D are4x4 matrices. The matrix multiply inputs A and B are FP16 matrices, while the accumulation matrices C and D may be FP16 or FP32 matrices.When accumulating in FP32, the FP16 multiply results in a full precision product that is then accumulated using FP32 addition with the other intermediate products for a 4x4x4 matrix multiply. In practice, Tensor Cores are used to perform much larger 2D or higher dimensional matrix operations, built up from these smaller elements.The Volta tensor cores are exposed as Warp-Level Matrix Operations in the CUDA 9 C++ API. The API exposes specialized matrix load, matrix multiply and accumulate, and matrix store operations to efficiently use Tensor Cores from a CUDA-C++ program. At the CUDA level, thewarp-level interface assumes 16x16 size matrices spanning all 32 threads of the warp. See the CUDA C++ Programming Guide for more information.1.4.3. Memory Throughput1.4.3.1. High Bandwidth MemoryGV100 uses up to eight memory dies per HBM2 stack and four stacks, with a maximum of 32 GB of GPU memory. A faster and more efficient HBM2 implementation delivers up to 900 GB/ s of peak memory bandwidth, compared to 732 GB/s for GP100. This combination of a new generation HBM2 memory, and a new generation memory controller, in Volta provides 1.5x delivered memory bandwidth, compared to Pascal GP100—and a greater than 95% memory bandwidth efficiency running many workloads.In order to hide the DRAM latencies at full HBM2 bandwidth more memory accesses mustbe kept in flight, compared to GPUs equipped with traditional GDDR5. This is accomplishedby the large complement of SMs in GV100, which typically boost the number of concurrent threads, and thus the reads-in-flight, compared to previous architectures. Resource-constrained kernels that are limited to low occupancy may benefit from increasing the number of concurrent memory accesses per thread.1.4.3.2. Unified Shared Memory/L1/Texture CacheIn Volta the L1 cache, texture cache, and shared memory are backed by acombined 128 KB data cache. As in previous architectures, such as Kepler,the portion of the cache dedicated to shared memory (known as the carveout)can be selected at runtime using cudaFuncSetAttribute() with the attribute cudaFuncAttributePreferredSharedMemoryCarveout. Volta supports shared memory capacities of 0, 8, 16, 32, 64, or 96 KB per SM.A new feature, Volta enables a single thread block to address the full 96 KB of shared memory. To maintain architectural compatibility, static shared memory allocations remain limited to 48 KB, and an explicit opt-in is also required to enable dynamic allocations above this limit. See the CUDA C++ Programming Guide for details.Like Pascal, Volta combines the functionality of the L1 and texture caches into a unified L1/ Texture cache which acts as a coalescing buffer for memory accesses, gathering up the data requested by the threads of a warp prior to delivery of that data to the warp.Volta increases the maximum capacity of the L1 cache to 128 KB, more than 7x larger than the GP100 L1. Another benefit of its union with shared memory, the Volta L1 improves in termsof both latency and bandwidth compared to Pascal. The result is that for many applications Volta narrows the performance gap between explicitly managed shared memory and direct access to device memory. Also, the cost of register spills is lowered compared to Pascal, and the balance of occupancy versus spilling should be re-evaluated to ensure best performance.1.4.4. Cooperative GroupsThe Volta architecture introduced Independent Thread Scheduling, which enables intra-warp synchronization patterns that were previously not possible. To efficiently expressthese new patterns, CUDA 9 introduces Cooperative Groups. This is an extension to the CUDA programming model for organizing groups of communicating threads. Cooperative Groups allows developers to express the granularity at which threads are communicating, helping them to express richer, more efficient parallel decompositions. See the CUDA C++ Programming Guide for more information.1.4.5. Multi-Process ServiceThe Volta Multi-Process Service is significantly improved compared to previous architecutres, both in terms of performance and robustness. Intermediary software schedulers, used for MPS with previous architectures, have been replaced by hardware accelerated units within the GPU. MPS clients now submit tasks directly to the GPU work queues, significantly decreasing submission latency and increasing aggregate throughput. The limit on the number of MPS clients has also been increased by 3x to 48. Volta MPS also provides each client with an isolated address space,3 and extends Unified Memory support for MPS applications.Volta MPS also provides control for clients to restrict each client to a fraction of the GPU execution resources. Developers can use this feature to reduce or eliminate head-of-line blocking where work from one MPS client overwhelms GPU execution resources and prevents other clients from making progress, and thus improve average latency and jitter accross the system.1.4.6. NVLink InterconnectNVLink is NVIDIA's high-speed data interconnect. NVLink can be used to significantly increase performance for both GPU-to-GPU communication and for GPU access to system memory. GV100 supports up to six NVLink connections with each connection carrying up to 50 GB/s of bi-directional bandwidth.NVLink operates transparently within the existing CUDA model. Transfers between NVLink-connected endpoints are automatically routed through NVLink, rather than PCIe. The cudaDeviceEnablePeerAccess() API call remains necessary to enable direct transfers (over either PCIe or NVLink) between GPUs. The cudaDeviceCanAccessPeer() can be used to determine if peer access is possible between any pair of GPUs.3As with previous architectures, MPS does not provide fatal fault isolation between clients.Appendix A.Revision HistoryVersion 1.0‣Initial Public ReleaseVersion 1.1‣Added Cooperative Groups section.‣Updated references to the CUDA C++ Programming Guide and CUDA C++ Best Practices Guide.NoticeThis document is provided for information purposes only and shall not be regarded as a warranty of a certain functionality, condition, or quality of a product. NVIDIA Corporation (“NVIDIA”) makes no representations or warranties, expressed or implied, as to the accuracy or completeness of the information contained in this document and assumes no responsibility for any errors contained herein. NVIDIA shall have no liability for the consequences or use of such information or for any infringement of patents or other rights of third parties that may result from its use. This document is not a commitment to develop, release, or deliver any Material (defined below), code, or functionality.NVIDIA reserves the right to make corrections, modifications, enhancements, improvements, and any other changes to this document, at any time without notice. Customer should obtain the latest relevant information before placing orders and should verify that such information is current and complete.NVIDIA products are sold subject to the NVIDIA standard terms and conditions of sale supplied at the time of order acknowledgement, unless otherwise agreed in an individual sales agreement signed by authorized representatives of NVIDIA and customer (“Terms of Sale”). NVIDIA hereby expressly objects to applying any customer general terms and conditions with regards to the purchase of the NVIDIA product referenced in this document. No contractual obligations are formed either directly or indirectly by this document.OpenCLOpenCL is a trademark of Apple Inc. used under license to the Khronos Group Inc.TrademarksNVIDIA and the NVIDIA logo are trademarks or registered trademarks of NVIDIA Corporation in the U.S. and other countries. Other company and product names may be trademarks of the respective companies with which they are associated.Copyright© -2021 NVIDIA Corporation & affiliates. All rights reserved.NVIDIA Corporation | 2788 San Tomas Expressway, Santa Clara, CA 95051。
基于线程队列动态规划法的GPU性能优化
基于线程队列动态规划法的GPU 性能优化魏雄1，2，胡倩1，王秋娴1，闫坤1，许萍萍3（1.武汉纺织大学数学与计算机学院，湖北武汉430000；2.国防科技大学计算机学院，湖南长沙410073；3.湖北城市建设职业技术学院，湖北武汉430205）收稿日期：2021-03-120引言GPU 在大数据和人工智能领域表现出惊人的计算能力，随着GPU 的普及，在生命科学、航空航天和国防中提供了较强的计算能力，特别是在2020年新冠肺炎基因序列测序和疫情传播预测等方面表现突出。
大数据和AI 时代的到来使计算任务加重，面对应用的不同资源需求，GPU 的资源单核未充分利用[1]。
为了解决GPU 资源利用率不足的问题，国内外学者提出一些方法，例如Justin Luitjens [1]提出了并发内核执行（CKE ）来支持在GPU 上并发运行多个内核，并且GPU 自身架构也支持线程级并行性（Thread-level Parallelism ，TLP ）[2]，但大量并发线程会导致严重的带宽问题，内存延迟而无法及时处理的内存请求有可能会导致流水线暂停，降低整体性能。
为了更好地提升性能，利用GPU 的资源，本文提出了线程队列动态规划法TQDP ，从线程角度出发，通过提高线程的执行次数和提升系统吞吐量，从而提高系统性能。
1GPU新一代GPU 体系架构集成的计算资源越来越多，同时由于GPU缺乏适当的体系架构来支持共享，需要软件、硬件或者软硬件协同的方法来使用计算资源，因其复杂性导致GPU 资源利用不足，影响整体性能。
1.1GPU体系架构NVIDIA第8代GPUTuring第一次使用GDDR6DRAM 内存，并引入了新的SM体系架构，采用了可加速光线追踪的RT Core，以及可用于AI推理的全新Tensor Core[3]。
虽然GPU 架构经过一代代的变化，但是大致架构改动不大。
图1是一个基线GPU架构图，GPU有多个流多处理器（Streaming Multiprocessor，SM），在每个SM中，计算资源包括算术逻辑单元（ALU）、特殊函数单元（SFU）以及寄存器，片上内存资源包括只读纹理缓存和常量缓存、L1数据缓存（D-cache）和共享内存。
恶劣电力线信道中的SOQPSK-MIL调制方法
恶劣电力线信道中的SOQPSK-MIL调制方法王永建;许俊峰;周渊;云晓春【摘要】为了能够更好地在恶劣电力线信道中传输信号,该文提出了一种新的整形偏移四相相移键控-军用(Shaped-offset quadrature phase-shift keying-Military,SOQPSK-MIL)调制方法.该调制算法中调制信号的波形与原有的Simon 定义的16个波形相比,在一个符号时间内波形的可能性只有8种.在解调过程中滤波器的个数减少为原来的一半,大大降低解调的复杂度,误码性能没有发生变化.给出了新的SOQPSK-MIL调制方法的解调过程.结合多径干扰条件下的电力线通信环境,可知该调制算法较适合在恶劣信道中使用.%In order to transmit signals with better quality in severe noise powerline channel, a new modulation method SOQPSK-MIL ( Shaped-offset quadrature phase-shift keying-Military) is proposed here. Compared with the method proposed by Simon which has 16 different waveforms, the new scheme has only half number waveforms. The number is reduced to half for the demodulation of the received signal through the less filter number. This shows that the modulation method is good for powerline channel with the merit of no performance degradation. The demodulation method is given here for the received signal. Compared with the noisy powerline communication environment, this method is fit for severe noisy channel.【期刊名称】《南京理工大学学报（自然科学版）》【年(卷),期】2012(036)001【总页数】5页(P61-65)【关键词】电力线信道;整形偏移四相相移键控-军用;网格图;维特比译码【作者】王永建;许俊峰;周渊;云晓春【作者单位】国家计算机网络应急技术处理协调中心,北京100029;国家计算机网络应急技术处理协调中心,北京100029;国家计算机网络应急技术处理协调中心,北京100029;国家计算机网络应急技术处理协调中心,北京100029【正文语种】中文【中图分类】TN957.51近年来关于电力线通信进行的研究主要集中在超宽带通信上［1－3］。
09-信息科学与电子工程专业英语(第2版)-吴雅婷-清华大学出版社
Technical English
For Information Science and Electronic Engineering
信息科学与电子工程专业英语
Unit 9
Digital Audio Compression
信息科学与电子工程专业英语
Part I
MPEG Audio Layer 3
sampler 样品 amplitude 幅度，广阔 stereo 立体声 modem 调制解调器 psycho-acoustic 心理声学的 threshold 门限，阈值 bitrate 比特率 bitcode 比特字，比特码 minority 少数 genre 流派，类型
3New Words Nhomakorabeacompressed.
音频信息是一种愈来愈多被下载的 （多媒体）形式，无论是乐队的唱片 选曲，无线电节目，还是视频伴音。
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The traditional method of storing digital audio, used in CDs and digital TV, samples the amplitude of the sound a set number of times per second, and records this.2
用于CD和数字电视中存储数字音频 的传统方法是每秒抽取并记录一定 次数的声音幅度值。
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The precision of the amplitude is determined by the number of bits used to store the amplitude. So the bandwidth (or memory) consumed by the audio signal is dependent on three factors: the number of samples taken per second (Frequency), the number of bits used to store the amplitude (Bit Depth) and the length of the signal (Time).
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指令带宽
− imagine依赖于一个4级的指令带宽层次：主机接口、memory、控制 存储单元和运算部件。 − 最高每个周期可以执行136条指令，其中不包括memory的load和 store指令。
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报告概要
背景知识的介绍 流处理器体系结构——imagine 流编程模型
− Kernel，stream − 指令集
一些专题讨论
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一些背景知识和概念的介绍
Media应用具有三个特点：
− 数据之间存在着大量的可并行性； − 数据的不可重用性； − 很高的计算与存储访问比。 这些特性导致了传统的标量的普通寄存器体系结构不适合，而需 要基于流的带宽有效的寄存器组织的体系结构。
scratch-pad寄存器文件
− 大小为128 word − 通过指令中指定的基地址加上局部寄存器中的偏移量来索引寻址。在 这里可以存储一些系数，小的数组，小的查询表和一些关于局部寄存 器的信息
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Imagine 流处理器体系结构(5)
功能运算部件
− 加法器和乘法器 流水操作。它们可以进行单精度浮点运算，32位的整型运算和16 位或8位并行的半整型操作。所有的乘法和浮点加运算都需要4个 周期的延迟，而整数加法及逻辑操作则需要1~2个周期。 − 除法和开方部件 不进行流水，只进行单精度浮点和32位整型操作。浮点除需要14 个周期，浮点开方为13个周期，而整数除法则需要21个周期。
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流编程模型
Imagine作为协处理器在两个层次上进行编程：内核级和应用 级。
一个流程序将数据组织成流的形式，而将所有的运算表示成 一个个内核功能块。
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CS 内核是一段程序，它反复地对输入的流中的每个数据元素进 行操作，产生一个输出流发送到下一个处理内核。
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一些背景知识和概念的介绍(cont.)
流编程模型
− 是将一个应用编码成一系列由数据片组成的流，在各个计算内核中对 流进行操作
Imagine体系结构
− Imagine围绕着一个128KB的流寄存器文件（SRF）来组织。对于编 程者来说，imagine就是个流的载入/存储体系结构：从存储器中将流 载入到SRF里，传送这些流到一系列的计算内核中进行操作，然后将 结果流存储回存储器。
Imagine 流处理器体系结构(3) ——运算簇（Cluster）
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Imagine 流处理器体系结构(4)
局部寄存器文件（LRF）
− 为各个功能部件提供输入数据。存储计算内核中的常量，参数以及局 部变量，减少对SRF带宽的要求 。 − 有着一个读端口和一个写端口。一个簇中共有17个这样的16字的LRF ，共可提供最高为54.4GB/s的数据带宽 。 − 分布的LRF组织结构相比于使用一个整块的寄存器文件，它在芯片尺 寸与速度上都有很大的提高。
Lecture on High Performance Processor Architecture (CS05162)
专题一：向量和流处理器 A Bandwidth-Efficient Architecture for Media Processing
2005.11.25 中国科学技术大学 计算机科学技术系
流，数据片，内核
− 流（stream）是一串相似的数据元素序列，其中的每个数据元素就是 一个数据片（record）。流的长度不定，主要可以有三种形式的流： 固定步幅的流（stride stream），索引流（indexed stream）和有条 件流（conditional stream）。数据片的长度大小不定，依具体的处 理实例确定。 − 内核（kernel）就是一段处理程序，功能上类似于C语言中的函数块 。它对数据流进行操作处理。
传统的体系结构的特点。
− 传统的存储系统依赖于cache，利用数据的重用性，优化延迟，不衡 量运算部件的数目和对寄存器的需求以支持一个高的计算/访存比。
VLSI技术
− 有着足够强的运算能力，受到的性能约束主要来自于通信带宽的有限 。在现代的VLSI技术中，挑战在于如何向众多的运算部件提供指令和 数据以充分利用资源
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流指令集
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内核实例
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应用级流编程示例
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一些讨论
imagine三层存储带宽结构
− Memory—SRF—LRFs − 1：32：272 − Memory带宽主要受限于芯片管脚的带宽，SRF的带宽则主要取决于 片上全局布线的可利用性，而LRF则主要是由ALU部件的数目决定了 它的带宽。
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Imagine 流处理器体系结构(6)
网络接口
− 提供四个双向的连接（每个连接带宽为400MB/s）。它可以被配置成 任意的拓扑结构连接多个imagine处理器。 − 使用网络接口进行互连通信，很容易地将一个应用划分成不同的任务 块，分散到多个imagine处理器上进行处理
主机接口
− 在一个指令窗口中缓存流出的应用级指令，直到某条指令的各种资源 要求和约束依赖关系满足时才将其流出。主机接口允许将imagine处 理器映射到主处理器的地址空间中，这样主处理器就可以读写 imagine存储器和将适当的应用级指令发送到imagine处理器上执行程 序。
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内核的编写使用C语言，遵循C的语法规则。它可能访问局部 数据，读取输入流和产生输出流，但绝对没有任何存储器访 问操作。内核被编译成微代码程序，对每个流元素有顺序的 使用运算簇中的部件而实现内核功能。
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stream
流是一串相似元素的序列。 流中的每个元素是一个数据片。数据片是一些相关的数据的 集合，长度大小不定。将流在各个计算内核中流动就构成了 整个流程序。 在应用级的编程中，编码使用的是C++语言的库调用，在主 处理器上执行。这些库调用通过使用流指令将操作指令传送 给imagine。
流存储系统
− 提供一个与片外SDRAM通信的1.6GB/s的带宽，它通过4个独立的32 位宽的通道来实现，工作频率为100MHz。 − 可以同时进行2个SRF与存储系统之间的流的传输，这个实现通过4个 流（2个索引流和2个数据流）连接存储系统和SRF完成。
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Imagine 流处理器体系结构
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Imagine 流处理器体系结构(2)
流寄存器文件(SRF)
− SRF是imagine流体系结构的组织核心部件，其他各个部分都通过它 来进行连接 。 − 大小128KB − 可以存储任意长度的任意数量的流。 − 流描述符，它包括流在SRF中的基地址，流的长度以及流中数据片的 大小。 − 18个64字宽的流缓冲器，允许18个流用户对其同时进行读或写访问。