计算机网络外文文献外文翻译英文文献新技术的计算机网络

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外文翻译--计算机

外文原文computerThe modern world of high technology could not have come about except for the development of the computer. Different types and sizes of computers find uses throughout society in the storage and handling of data, from secret governmental files to banking transactions to private household accounts. Computers have opened up a new era in manufacturing through the techniques of automation, and they have enhanced modern communication systems. They are essential tools in almost every field of research and applied technology, from constructing models of the universe to producing tomorrow’s weather reports, and technique use has in itself opened up new areas of conjecture. Database services and computer networks make available a great variety of information sources. The same advanced techniques also make the invasions of privacy and restricted information sources possible, and computer crime has become one of the many risks that society must face if it is to enjoy the benefits of modern technology.A computer is an electronic device that can receive a set of instructions, or program, and then carry out this program by performing calculations on numerical data or by compiling and correlating other forms of information. The type of computers are mainly inclusive of Microcomputer, Minicomputer, Mainframe Computer and Supercomputer, etc. Microminiaturization , the effort to compress more circuit elements into smaller and smaller chip space is becoming the major trend in computer development. Besides, researchers are trying to develop more powerful and more advanced computers.Any customers all pass the operate system to use the calculator, not direct carry on the operation to the hardware of the calculators. The operate system is a bridge that communicates the customer and calculator. Every general-purpose computer must have an operating system to run other programs. Operating systems perform basic tasks and provide a software platform. The choice of operating systems determines to a great extent of the applications. Therefore OS is very important.The operate system is in the charge of Computer resource control program to execute system software. Say in a specific way，the OS is the most basic in the calculator software system, also constituting the part most importantly, it is responsible for the management and controls the calculator system in all hardware resources and the software resources, can make of various resources matched with mutually, moderating to work with one accord, full develop its function, exaltation the efficiency of the system, still take the interface function of the customer and the calculator system at the same time, use the calculator to provide the convenience for the customer. The operate system is a huge management control procedure, including 5 management functions mostly: Progress and processing the machine manage, the homework manage, saving management, equipments management, document management. Divide the line from the function, the tiny machine operate system can is divided into the single mission operate system, single many mission operate systems of customer and many mission operate systems of multi-user of single customer. At present there are several kinds of OS on the computer which are DOS, OS/2, UNIX, XENIX, LINUX, Window2000, Netware etc.In order for a computer to perform the required task, it must be given instructions in a language that it understands. However, the computer’s own binary based language, or machine language, is difficult for humans to use. Therefore, people devised an assembly language to shorten and simplify the process. In order to make a computer more friendly to use, programmers invented high level languages, such as COBOL, FORTRAN, ASSEMBLER, PASCAL, C++, etc, which made the computers easier to use. For the time being, HTML and XML are very useful languages as well.The database is often used to describe a collection of related data that is organized into an integrated, sophisticated structure that provides different people with varied access to the same data. A database management system is an extremely complex set of software programs that controls the organization, storage and retrieval of data in a database. A successful DBMS is often characterized with the four principal features: (1)Data Security and Integrity; (2)Interactive query; (3)Interactive data Entry and Updating; (4)Data Independence. The intelligent databases are becoming more popular in that they canprovide more validation. The researches on new types of database systems are underway.计算机倘若不是伴随着计算机的发展，现代世界的高端技术不可能出现。

计算机网络外文翻译

附录一、英文原文：The NetWorksBirth of the NetThe Internet has had a relatively brief, but explosive history so far. It grew out of an experiment begun in the 1960's by the U.S. Department of Defense. The DoD wanted to create a computer network that would continue to function in the event of a disaster, such as a nuclear war. If part of the network were damaged or destroyed, the rest of the system still had to work. That network was ARPANET, which linked U.S. scientific and academic researchers. It was the forerunner of today's Internet.In 1985, the National Science Foundation (NSF) created NSFNET, a series of networks for research and education communication. Based on ARPANET protocols, the NSFNET created a national backbone service, provided free to any U.S. research and educational institution. At the same time, regional networks were created to link individual institutions with the national backbone service.NSFNET grew rapidly as people discovered its potential, and as new software applications were created to make access easier. Corporations such as Sprint and MCI began to build their own networks, which they linked to NSFNET. As commercial firms and other regional network providers have taken over the operation of the major Internet arteries, NSF has withdrawn from the backbone business.NSF also coordinated a service called InterNIC, which registered all addresses on the Internet so that data could be routed to the right system. This service has now been taken over by Network Solutions, Inc., in cooperation with NSF.How the Web WorksThe World Wide Web, the graphical portion of the Internet, is the most popular part of the Internet by far. Once you spend time on the Web,you will begin to feel like there is no limit to what you can discover. The Web allows rich and diverse communication by displaying text, graphics, animation, photos, sound and video.So just what is this miraculous creation? The Web physically consists of your personal computer, web browser software, a connection to an Internet service provider, computers called servers that host digital data and routers and switches to direct the flow of information.The Web is known as a client-server system. Your computer is the client; the remote computers that store electronic files are the servers. Here's how it works: Let's say you want to pay a visit to the the Louvre museum website. First you enter the address or URL of the website in your web browser (more about this shortly). Then your browser requests the web page from the web server that hosts the Louvre's site. The Louvre's server sends the data over the Internet to your computer. Your webbrowser interprets the data, displaying it on your computer screen.The Louvre's website also has links to the sites of other museums, such as the VaticanMuseum. When you click your mouse on a link, you access the web server for the VaticanMuseum.The "glue" that holds the Web together is called hypertext and hyperlinks. This feature allow electronic files on the Web to be linked so you can easily jump between them. On the Web, you navigate through pages of information based on what interests you at that particular moment, commonly known as browsing or surfing the Net.To access the Web you need web browser software, such as Netscape Navigator or Microsoft Internet Explorer. How does your web browser distinguish between web pages and other files on the Internet? Web pages are written in a computer language called Hypertext Markup Language or HTML.Some Web HistoryThe World Wide Web (WWW) was originally developed in 1990 at CERN, the European Laboratory for Particle Physics. It is now managed by The World Wide Web Consortium, also known as the World Wide Web Initiative.The WWW Consortium is funded by a large number of corporate members, including AT&T, Adobe Systems, Inc., Microsoft Corporation and Sun Microsystems, Inc. Its purpose is to promote the growth of the Web by developing technical specifications and reference software that will be freely available to everyone. The Consortium is run by MIT with INRIA (The French National Institute for Research in Computer Science) acting as European host, in collaboration with CERN.The NationalCenter for Supercomputing Applications (NCSA) at the University of Illinois at Urbana-Champaign, was instrumental in the development of early graphical software utilizing the World Wide Web features created by CERN. NCSA focuses on improving the productivity of researchers by providing software for scientific modeling, analysis, and visualization. The World Wide Web was an obvious way to fulfill that mission. NCSA Mosaic, one of the earliest web browsers, was distributed free to the public. It led directly to the phenomenal growth of the World Wide Web.Understanding Web AddressesYou can think of the World Wide Web as a network of electronic files stored on computers all around the world. Hypertext links these resources together. Uniform Resource Locators or URLs are the addresses used to locate these files. The information contained in a URL gives you the ability to jump from one web page to another with just a click of your mouse. When you type a URL into your browser or click on a hypertext link, your browser is sending a request to a remote computer to download a file.What does a typical URL look like? Here are some examples:/The home page for study english.ftp:///pub/A directory of files at MIT* available for downloading.news:rec.gardens.rosesA newsgroup on rose gardening.The first part of a URL (before the two slashes* tells you the type of resource or method of access at that address. For example:·http - a hypertext document or directory·gopher - a gopher document or menu·ftp - a file available for downloading or a directory of such files·news - a newsgroup·telnet - a computer system that you can log into over the Internet·WAIS* - a database or document in a Wide Area Information Search database ·file - a file located on a local drive (your hard drive)The second part is typically the address of the computer where the data or service is located. Additional parts may specify the names of files, the port to connect to, or the text to search for in a database.You can enter the URL of a site by typing it into the Location bar of your web browser, just under the toolbar.Most browsers record URLs that you want to use again, by adding them to a special menu. In Netscape Navigator, it's called Bookmarks. In Microsoft Explorer, it's called Favorites. Once you add a URL to your list, you can return to that web page simply by clicking on the name in your list, instead of retyping the entire URL.Most of the URLs you will be using start with http which stands for Hypertext Transfer Protocol*. http is the method by which HTML files are transferred over the Web. Here are some other important things to know about URLs:· A URL usually has no spaces.· A URL always uses forward slashes (//).If you enter a URL incorrectly, your browser will not be able to locate the site or resource you want. Should you get an error message or the wrong site, make sure you typed the address correctly.You can find the URL behind any link by passing your mouse cursor over the link. The pointer will turn into a hand and the URL will appear in the browser's status bar, usually located at the bottom of your screen.Domain NamesWhen you think of the Internet, you probably think of ".com." Just what do those three letters at the end of a World Wide Web address mean?Every computer that hosts data on the Internet has a unique numerical address. For example, the numerical address for the White House is 198.137.240.100. But since few people want to remember long strings of numbers, the Domain Name System (DNS)* was developed. DNS, a critical part of the Internet's technical infrastructure*, correlates* a numerical address to a word. To access the White House website, you could type its number into the address box of your web browser. But most people prefer to use "." In this case, the domain name is .In general, the three-letter domain name suffix* is known as a generic top-level domain and describes the type of organization. In the last few years, the lines have somewhat blurred* between these categories..com - business (commercial).edu - educational.org - non-profit.mil - military.net - network provider.gov - governmentA domain name always has two or more parts separated by dots and typically consists of some form of an organization's name and the three-letter suffix. For example, the domain name for IBM is ""; the United Nations is "."If a domain name is available, and provided it does not infringe* on an existing trademark, anyone can register the name for $35 a year through Network Solutions, Inc., which is authorized to register .com, .net and .org domains. You can use the box below to see if a name is a available. Don't be surprised if the .com name you want is already taken, however. Of the over 8 million domain names, 85% are .com domains.ICANN, the Internet Corporation for Assigned Names and Numbers, manages the Domain Name System. As of this writing, there are plans to add additional top-level domains, such as .web and .store. When that will actually happen is anybody's guess.To check for, or register a domain name, type it into the search box.It should take this form: In addition to the generic top-level domains, 244 national top-level domains were established for countries and territories*, for example:.au - Australia.ca - Canada.fr - France.de - Germany.uk - United KingdomFor US $275 per name, you can also register an international domain name with Net Names. Be aware that some countries have restrictions for registering names.If you plan to register your own domain name, whether it's a .com or not, keep these tips in mind:The shorter the name, the better. (But it should reflect your family name, interest or business.)The name should be easy to remember.It should be easy to type without making mistakes.Remember, the Internet is global. Ideally, a domain name will "read" in a language other than English.Decoding Error MessagesAs you surf the Net, you will undoubtedly find that at times you can't access certain websites. Why, you make wonder? Error messages attempt to explain thereason. Unfortunately, these cryptic* messages baffle* most people. We've deciphered* the most common ones you may encounter.400 - Bad RequestProblem: There's something wrong with the address you entered. You may not be authorized* to access the web page, or maybe it no longer exists.Solution: Check the address carefully, especially if the address is long. Make sure that the slashes are correct (they should be forward slashes) and that all the names are properly spelled. Web addresses are case sensitive, so check that the names are capitalized in your entry as they are in the original reference to the website.401 - UnauthorizedProblem: You can't access a website, because you're not on the guest list, your password is invalid or you have entered your password incorrectly.Solution: If you think you have authorization, try typing your password again. Remember that passwords are case sensitive.403 - ForbiddenProblem: Essentially the same as a 401.Solution: Try entering your password again or move on to another site.404 - Not FoundProblem: Either the web page no longer exists on the server or it is nowhere to be found.Solution: Check the address carefully and try entering it again. You might also see if the site has a search engine and if so, use it to hunt for the document. (It's not uncommon for pages to change their addresses when a website is redesigned.) To get to the home page of the site, delete everything after the domain name and hit the Enter or Return key.503 - Service unavailableProblem: Your Internet service provider (ISP) or your company's Internet connection may be down.Solution: Take a stretch, wait a few minutes and try again. If you still have no luck, phone your ISP or system administrator.Bad file requestProblem: Your web browser may not be able to decipher the online form you want to access. There may also be a technical error in the form.Solution: Consider sending a message to the site's webmaster, providing any technical information you can, such as the browser and version you use.Connection refused by hostProblem: You don't have permission to access the page or your password is incorrect.Solution: Try typing your password again if you think you should have access.Failed DNS lookupProblem: DNS stands for the Domain Name System, which is the system that looks up the name of a website, finds a corresponding number (similar to a phone number), then directs your request to the appropriate web server on the Internet. When the lookup fails, the host server can't be located.Solution: Try clicking on the Reload or Refresh button on your browser toolbar. If this doesn't work, check the address and enter it again. If all else fails, try again later.File contains no dataProblem: The site has no web pages on it.Solution: Check the address and enter it again. If you get the same error message, try again later.Host unavailableProblem: The web server is down.Solution: Try clicking on the Reload or Refresh button. If this doesn't work, try again later.Host unknownProblem: The web server is down, the site may have moved, or you've been disconnected from the Net.Solution: Try clicking on the Reload or Refresh button and check to see that you are still online. If this fails, try using a search engine to find the site. It may have a new address.Network connection refused by the serverProblem: The web server is busy.Solution: Try again in a while.Unable to locate hostProblem: The web server is down or you've been disconnected from the Net.Solution: Try clicking on the Reload or Refresh button and check to see that you are still online.Unable to locate serverProblem: The web server is out-of-business or you may have entered the addressincorrectly.Solution: Check the address and try typing it again.二、英文翻译：网络网络的诞生迄今为止，因特网的历史虽比较简短，但仍然是突破性的。

计算机专业外文文献翻译6

外文文献翻译（译成中文2000字左右）：As research laboratories become more automated,new problems are arising for laboratory managers.Rarely does a laboratory purchase all of its automation from a single equipment vendor. As a result,managers are forced to spend money training their users on numerous different software packages while purchasing support contracts for each. This suggests a problem of scalability. In the ideal world,managers could use the same software package to control systems of any size; from single instruments such as pipettors or readers to large robotic systems with up to hundreds of instruments. If such a software package existed, managers would only have to train users on one platform and would be able to source software support from a single vendor.If automation software is written to be scalable, it must also be flexible. Having a platform that can control systems of any size is far less valuable if the end user cannot control every device type they need to use. Similarly, if the software cannot connect to the customer’s Laboratory Information Management System (LIMS) database,it is of limited usefulness. The ideal automation software platform must therefore have an open architecture to provide such connectivity.Two strong reasons to automate a laboratory are increased throughput and improved robustness. It does not make sense to purchase high-speed automation if the controlling software does not maximize throughput of the system. The ideal automation software, therefore, would make use of redundant devices in the system to increase throughput. For example, let us assume that a plate-reading step is the slowest task in a given method. It would make that if the system operator connected another identical reader into the system, the controller software should be able to use both readers, cutting the total throughput time of the reading step in half. While resource pooling provides a clear throughput advantage, it can also be used to make the system more robust. For example, if one of the two readers were to experience some sort of error, the controlling software should be smart enough to route all samples to the working reader without taking the entire system offline.Now that one embodiment of an ideal automation control platform has been described let us see how the use of C++ helps achieving this ideal possible.DISCUSSIONC++: An Object-Oriented LanguageDeveloped in 1983 by BjarneStroustrup of Bell Labs,C++ helped propel the concept of object-oriented programming into the mainstream.The term ‘‘object-oriented programming language’’ is a familiar phrase that has been in use for decades. But what does it mean? And why is it relevant for automation software? Essentially, a language that is object-oriented provides three important programming mechanisms:encapsulation, inheritance, and polymorphism.Encapsulation is the ability of an object to maintain its own methods (or functions) and properties (or variables).For example, an ‘‘engine’’ object might contain methods for starting, stopping, or accelerating, along with properties for ‘‘RPM’’ and ‘‘Oil pressure’’. Further, encapsulation allows an object to hide private data from a ny entity outside the object. The programmer can control access to the object’s data by marking methods or properties as public, protected,or private. This access control helps abstract away the inner workings of a class while making it obvious to a caller which methods and properties are intended to be used externally.Inheritance allows one object to be a superset of another object. For example, one can create an object called Automobile that inherits from Vehicle. The Automobile object has access to all non-private methods and properties of Vehicle plus any additional methods or properties that makes it uniquely an automobile.Polymorphism is an extremely powerful mechanism that allows various inherited objects to exhibit different behaviors when the same named method is invoked upon them. For example, let us say our Vehicle object contains a method called CountWheels. When we invoke this method on our Automobile, we learn that the Automobile has four wheels.However, when we call this method on an object called Bus,we find that the Bus has 10 wheels.Together, encapsulation, inheritance, and polymorphism help promote code reuse, which is essential to meeting our requirement that the software package be flexible. A vendor can build up a comprehensive library of objects (a serial communications class, a state machine class, a device driver class,etc.) that can be reused across many different code modules.A typical control software vendor might have 100 device drivers. It would be a nightmare if for each of these drivers there were no building blocks for graphical user interface (GUI) or communications to build on. By building and maintaining a library of foundation objects, the vendor will save countless hours of programming and debugging time.All three tenets of object-oriented programming are leveraged by the use of interfaces. An interface is essentially a specification that is used to facilitate communication between software components, possibly written by different vendors. An interface says, ‘‘if your cod e follows this set of rules then my software component will be able to communicate with it.’’ In the next section we will see how interfaces make writing device drivers a much simpler task.C++ and Device DriversIn a flexible automation platform, one optimal use for interfaces is in device drivers. We would like our open-architecture software to provide a generic way for end users to write their own device drivers without having to divulge the secrets of our source code to them. To do this, we define a simplifiedC++ interface for a generic device, as shown here:class IDevice{public:virtual string GetName() ? 0; //Returns the name//of the devicevirtual void Initialize() ? 0; //Called to//initialize the devicevirtual void Run() ? 0; // Called to run the device};In the example above, a Ctt class (or object) called IDevice has been defined. The prefix I in IDevice stands for ‘‘interface’’. This class defines three public virtual methods: GetName, Initialize, and Run. The virtual keyword is what enables polymorphism, allowing the executing program to run the methods of the inheriting class. When a virtual method declaration is suffixed with ?0, there is no base class implementation. Such a method is referred to as ‘‘pure virtual’’. A class like IDevice that contains only pure virtual functions is known as an ‘‘abstract class’’, or an‘‘interface’’. The IDevice definition, along with appropriate documentation, can be published to the user community,allowing developers to generate their own device drivers that implement the IDevice interface.Suppose a thermal plate sealer manufacturer wants to write a driver that can be controlled by our software package. They would use inheritance to implement our IDevice interface and then override the methods to produce the desired behavior: class CSealer : public IDevice{public:virtual string GetName() {return ‘‘Sealer’’;}virtual void Initialize() {InitializeSealer();}virtual void Run() {RunSealCycle();}private:void InitializeSealer();void RunSealCycle();};Here the user has created a new class called CSealer that inherits from the IDevice interface. The public methods,those that are accessible from outside of the class, are the interface methods defined in IDevice. One, GetName, simply returns the name of the device type that this driver controls.The other methods,Initialize() and Run(), call private methods that actually perform the work. Notice how the privatekeyword is used to prevent external objects from calling InitializeSealer() and RunSealCycle() directly.When the controlling software executes, polymorphism will be used at runtime to call the GetName, Initialize, and Run methods in the CSealer object, allowing the device defined therein to be controlled.DoSomeWork(){//Get a reference to the device driver we want to useIDevice&device ? GetDeviceDriver();//Tell the world what we’re about to do.cout !! ‘‘Initializing ’’!! device.GetName();//Initialize the devicedevice.Initialize();//Tell the world what we’re about to do.cout !! ‘‘Running a cycle on ’’ !!device.GetName();//Away we go!device.Run();}The code snippet above shows how the IDevice interface can be used to generically control a device. If GetDevice-Driver returns a reference to a CSealer object, then DoSomeWork will control sealers. If GetDeviceDriver returns a reference to a pipettor, then DoSomeWork will control pipettors. Although this is a simplified example, it is straightforward to imagine how the use of interfaces and polymorphism can lead to great economies of scale in controller software development.Additional interfaces can be generated along the same lines as IDevice. For example, an interface perhaps called ILMS could be used to facilitate communication to and from a LIMS.The astute reader will notice that the claim that anythird party can develop drivers simply by implementing the IDevice interface is slightly flawed. The problem is that any driver that the user writes, like CSealer, would have to be linked directly to the controlling software’s exec utable to be used. This problem is solved by a number of existing technologies, including Microsoft’s COMor .NET, or by CORBA. All of these technologies allow end users to implement abstract interfaces in standalone components that can be linked at runtime rather than at design time. The details are beyond the scope of this article.中文翻译：随着研究实验室更加自动化，实验室管理人员出现的新问题。

计算机英文文献加翻译

Management Information System Overview Management Information System is that we often say that the MIS, is a human, computers and other information can be composed of the collection, transmission, storage, maintenance and use of the system, system, emphasizing emphasizing the the management, management, management, stressed stressed stressed that that the modern information society In the increasingly popular. MIS is a new subject, it across a number of areas, such as scientific scientific management management management and and and system system system science, science, science, operations operations operations research, research, research, statistics statistics statistics and and and computer computer science. In these subjects on the basis of formation of information-gathering and processing methods, thereby forming a vertical and horizontal weaving, and systems. The 20th century, along with the vigorous development of the global economy, many economists have proposed a new management theory. In the 1950s, Simon made dependent on information management and decision-making ideas. Wiener published the same period of the control theory, that he is a management control process. 1958, Gail wrote: "The management will lower the cost of timely and accurate information to b etter control." During better control." During this period, accounting for the beginning of the computer, data processing in the term.1970, Walter T . Kenova just to the management information system under a definition of the . Kenova just to the management information system under a definition of the term: "verbal or written form, at the right time to managers, staff and outside staff for the past, present, the projection of future Enterprise and its environment-related information 原文请找腾讯3249114六,维^论~文.网 no no application application application model, model, model, no no mention mention of of computer applications. 1985, management information systems, the founder of the University of Minnesota professor of management at the Gordon B. Davis to a management information system a more complete definition of "management information system is a computer hardware and software resources, manual operations, analysis, planning , Control and decision -making model and the database - System. System. It It provides information to to support support enterprises enterprises or or organizations organizations of of the operation, management and decision-making function. "Comprehensive definition of this Explained Explained that that that the the the goal goal goal of of of management management management information information information system, system, system, functions functions functions and and and composition, composition, composition, but but also reflects the management information system at the time of level.With the continuous improvement of science and technology, computer science increasingly mature, the computer has to be our study and work on the run along. Today, computers are already already very low price, performance, but great progress, and it was used in many areas, the very low price, performance, but great progress, and it was used in many areas, the computer computer was was was so so so popular popular popular mainly mainly mainly because because because of of of the the the following following following aspects: aspects: aspects: First, First, First, the the the computer computer computer can can substitute for many of the complex Labor. Second, the computer can greatly enhance people's work work efficiency. efficiency. efficiency. Third, Third, Third, the the the computer computer computer can can can save save save a a a lot lot lot of of of resources. resources. resources. Fourth, Fourth, Fourth, the the the computer computer computer can can make sensitive documents more secure.Computer application and popularization of economic and social life in various fields. So that the original old management methods are not suited now more and social development. Many people still remain in the previous manual. This greatly hindered the economic development of mankind. mankind. In recent years, with the University of sponsoring scale is In recent years, with the University of sponsoring scale is growing, the number of students students in in in the the the school school school also also also have have have increased, increased, increased, resulting resulting resulting in in in educational educational educational administration administration administration is is is the the growing complexity of the heavy work, to spend a lot of manpower, material resources, and the existing management of student achievement levels are not high, People have been usin g the traditional method of document management student achievement, the management there are many shortcomings, such as: low efficiency, confidentiality of the poor, and Shijianyichang, will have a large number of of documents documents documents and and data, which is is useful useful for finding, finding, updating updating and maintaining Have brought a lot of difficulties. Such a mechanism has been unable to meet the development of the times, schools have become more and more day -to-day management of a bottleneck. bottleneck. In In In the the the information information information age age age this this this traditional traditional traditional management management management methods methods methods will will will inevitably inevitably inevitably be be computer-based information management replaced. As As part part part of of of the the the computer computer computer application, application, application, the the the use use use of of of computers computers computers to to to students students students student student student performance performance information for management, with a manual management of the incomparable advantages for example: example: rapid rapid rapid retrieval, retrieval, retrieval, to to to find find find convenient, convenient, convenient, high high high reliability reliability reliability and and and large large large capacity capacity capacity storage, storage, storage, the the confidentiality confidentiality of of of good, good, good, long long long life, life, life, cost cost cost Low. Low. Low. These These These advantages advantages advantages can can can greatly greatly greatly improve improve improve student student performance management students the efficiency of enterprises is also a scientific, standardized standardized management, management, management, and and and an an an important important important condition condition condition for for for connecting connecting connecting the the the world. world. world. Therefore, Therefore, the development of such a set of management software as it is very necessary thing.Design ideas are all for the sake of users, the interface nice, clear and simple operation as far as possible, but also as a practical operating system a good fault-tolerant, the user can misuse a timely manner as possible are given a warning, so that users timely correction . T o take full advantage advantage of the of the functions of visual FoxPro, design p owerful software powerful software at the same time, as much as possible to reduce the occupiers system resources. Visual FoxPro the command structure and working methods: Visual FoxPro was originally originally called called FoxBASE, FoxBASE, the the U.S. U.S. Fox Fox Software has introduced introduced a a database products, products, in in the run on DOS, compatible with the abase family. Fox Fox Software Software Microsoft acquisition, to be developed so that it can run on Windows, and changed its name to Visual FoxPro. Visual FoxPro is a powerful relational database rapid application development tool, tool, the the the use use use of of of Visual Visual Visual FoxPro FoxPro FoxPro can can can create create create a a a desktop desktop desktop database database database applications, applications, applications, client client client / / / server server applications applications and and and Web Web Web services services services component-based component-based component-based procedures, procedures, procedures, while while while also also also can can can use use use ActiveX ActiveX controls or API function, and so on Ways to expand the functions of Visual FoxPro.1651First, work methods 1. Interactive mode of operation (1) order operation VF in the order window, through an order from the keyboard input of all kinds of ways to complete the operation order. (2) menu operation VF use menus, windows, dialog to achieve the graphical interface features an interactive operation. (3) aid operation VF in the system provides a wide range of user-friendly operation of tools, such as the wizard, design, production, etc.. 2. Procedure means of implementation VF in the implementation of the procedures is to form a group of orders and programming language, an extension to save. PRG procedures in the document, and then run through the automatic implementation of this order documents and award results are displayed. Second, the structure of command 1. Command structure 2. VF orders are usually composed of two parts: The first part is the verb order, also known as keywords, for the operation of the designated order functions; second part of the order clause, for an order that the operation targets, operating conditions and other information . VF order form are as follows: 3. <Order verb> "<order clause>" 4. Order in the format agreed symbols 5. 5. VF in the order form and function of the use of the symbol of the unity agreement, the meaning of VF in the order form and function of the use of the symbol of the unity agreement, the meaning of these symbols are as follows: 6. Than that option, angle brackets within the parameters must be based on their format input parameters. 7. That may be options, put in brackets the parameters under specific requ ests from users choose to enter its parameters. 8. Third, the project manager 9. Create a method 10. command window: CREA T PROJECT <file name> T PROJECT <file name> 11. Project Manager 12. tab 13. All - can display and project management applications of all types of docume nts, "All" tab contains five of its right of the tab in its entirety . 14. Data - management application projects in various types of data files, databases, free form, view, query documents. 15. Documentation - display 原文请找腾讯原文请找腾讯3249114六,维^论~文.网 , statements, documents, labels and other documents. 16. Category - the tab display and project management applications used in the class library documents, including VF's class library system and the user's own design of the library. 17. Code - used in the project management procedures code documents, such as: program files (. PRG), API library and the use of project management for generation of applications (. APP). 18. (2) the work area 19. The project management work area is displayed and management of all types of document window. 20. (3) order button 21. Project Manager button to the right of the order of the work area of the document window to provide command. 22. 4, project management for the use of 23. 1. Order button function 24. New - in the work area window selected certain documents, with new orders button on the new document added to the project management window. 25. Add - can be used VF "file" menu under the "new" order and the "T ools" menu under the "Wizard" order to create the various independent paper added to the project manager, unified organization with management. 26. Laws - may amend the project has been in existence in the various documents, is still to use such documents to modify the design interface. 27. Sports - in the work area window to highlight a specific document, will run the paper.28. Mobile - to check the documents removed from the project. 29. 29. Even Even Even the the the series series series - - - put put put the the the item item item in in in the the the relevant relevant relevant documents documents documents and and and even even even into into into the the the application application executable file. Database System Design :Database design is the logical database design, according to a forthcoming data classification system and the logic of division-level organizations, is user-oriented. Database design needs of various departments of the integrated enterprise archive data and data needs analysis of the relationship between the various data, in accordance with the DBMS. 管理信息系统概要管理信息系统概要管理信息系统就是我们常说的MIS （Management Information System ），是一个由人、计算机等组成的能进行信息的收集、传送、储存、维护和使用的系统，在强调管理，强调信息的现代社会中它越来越得到普及。

计算机专业毕业论文外文翻译

附录（英文翻译）Rich Client Tutorial Part 1The Rich Client Platform (RCP) is an exciting new way to build Java applications that can compete with native applications on any platform. This tutorial is designed to get you started building RCP applications quickly. It has been updated for Eclipse 3.1.2By Ed Burnette, SASJuly 28, 2004Updated for 3.1.2: February 6, 2006IntroductionTry this experiment: Show Eclipse to some friends or co-workers who haven't seen it before and ask them to guess what language it is written in. Chances are, they'll guess VB, C++, or C#, because those languages are used most often for high quality client side applications. Then watch the look on their faces when you tell them it was created in Java, especially if they are Java programmers.Because of its unique open source license, you can use the technologies that went into Eclipse to create your own commercial quality programs. Before version 3.0, this was possible but difficult, especially when you wanted to heavily customize the menus, layouts, and other user interface elements. That was because the "IDE-ness" of Eclipse was hard-wired into it. Version 3.0 introduced the Rich Client Platform (RCP), which is basically a refactoring of the fundamental parts of Eclipse's UI, allowing it to be used for non-IDE applications. Version 3.1 updated RCP with new capabilities, and, most importantly, new tooling support to make it easier to create than before.If you want to cut to the chase and look at the code for this part you can find it in the accompanying zip file. Otherwise, let's take a look at how to construct an RCP application.Getting startedRCP applications are based on the familiar Eclipse plug-in architecture, (if it's not familiar to you, see the references section). Therefore, you'll need to create a plug-in to be your main program. Eclipse's Plug-in Development Environment (PDE) provides a number of wizards and editors that take some of the drudgery out of the process. PDE is included with the Eclipse SDK download so that is the package you should be using. Here are the steps you should follow to get started.First, bring up Eclipse and select File > New > Project, then expand Plug-in Development and double-click Plug-in Project to bring up the Plug-in Project wizard. On the subsequent pages, enter a Project name such as org.eclipse.ui.tutorials.rcp.part1, indicate you want a Java project, select the version of Eclipse you're targeting (at least 3.1), and enable the option to Create an OSGi bundle manifest. Then click Next >.Beginning in Eclipse 3.1 you will get best results by using the OSGi bundle manifest. In contrast to previous versions, this is now the default.In the next page of the Wizard you can change the Plug-in ID and other parameters. Of particular importance is the question, "Would you like to create a rich client application?". Select Yes. The generated plug-in class is optional but for this example just leave all the other options at their default values. Click Next > to continue.If you get a dialog asking if Eclipse can switch to the Plug-in Development Perspective click Remember my decision and select Yes (this is optional).Starting with Eclipse 3.1, several templates have been provided to make creating an RCP application a breeze. We'll use the simplest one available and see how it works. Make sure the option to Create a plug-in using one of the templates is enabled, then select the Hello RCP template. This isRCP's equivalent of "Hello, world". Click Finish to accept all the defaults and generate the project (see Figure 1). Eclipse will open the Plug-in Manifest Editor. The Plug-in Manifest editor puts a friendly face on the various configuration files that control your RCP application.Figure 1. The Hello World RCP project was created by a PDE wizard.Taking it for a spinTrying out RCP applications used to be somewhat tedious. You had to create a custom launch configuration, enter the right application name, and tweak the plug-ins that were included. Thankfully the PDE keeps track of all this now. All you have to do is click on the Launch an Eclipse Application button in the Plug-in Manifest editor's Overview page. You should see a bare-bones Workbench start up (see Figure 2).Figure 2. By using thetemplates you can be up andrunning anRCPapplication inminutes.Making it aproductIn Eclipse terms a product is everything that goes with your application, including all the other plug-ins it depends on, a command to run the application (called the native launcher), and any branding (icons, etc.) that make your application distinctive. Although as we've just seen you can run a RCP application without defining a product, having one makes it a whole lot easier to run the application outside of Eclipse. This is one of the major innovations that Eclipse 3.1 brought to RCP development.Some of the more complicated RCP templates already come with a product defined, but the Hello RCP template does not so we'll have to make one.In order to create a product, the easiest way is to add a product configuration file to the project. Right click on the plug-in project and select New > Product Configuration. Then enter a file name for this new configuration file, such as part1.product. Leave the other options at their default values. Then click Finish. The Product Configuration editor will open. This editor lets you control exactly what makes up your product including all its plug-ins and branding elements.In the Overview page, select the New... button to create a new product extension. Type in or browse to the defining plug-in(org.eclipse.ui.tutorials.rcp.part1). Enter a Product ID such as product, and for the Product Application selectorg.eclipse.ui.tutorials.rcp.part1.application. Click Finish to define the product. Back in the Overview page, type in a new Product Name, for example RCP Tutorial 1.In Eclipse 3.1.0 if you create the product before filling inthe Product Name you may see an error appear in the Problems view. The error will go away when you Synchronize (see below). This is a known bug that is fixed in newer versions. Always use the latest available maintenance release for the version of Eclipse you're targeting!Now select the Configuration tab and click Add.... Select the plug-in you just created (org.eclipse.ui.tutorials.rcp.part1) and then click on Add Required Plug-ins. Then go back to the Overview page and press Ctrl+S or File > Save to save your work.If your application needs to reference plug-ins that cannot be determined until run time (for example the tomcat plug-in), then add them manually in the Configuration tab.At this point you should test out the product to make sure it runs correctly. In the Testing section of the Overview page, click on Synchronize then click on Launch the product. If all goes well, the application should start up just like before.Plug-ins vs. featuresOn the Overview page you may have noticed an option that says the product configuration is based on either plug-ins or features. The simplest kind of configuration is one based on plug-ins, so that's what this tutorial uses. If your product needs automatic update or Java Web Start support, then eventually you should convert it to use features. But take my advice and get it working without them first.Running it outside of EclipseThe whole point of all this is to be able to deploy and run stand-alone applications without the user having to know anything about the Java and Eclipse code being used under the covers. For a real application you may want to provide a self-contained executable generated by an install program like InstallShield or NSIS. That's really beyond the scope of this article though, so we'll do something simpler.The Eclipse plug-in loader expects things to be in a certain layout so we'll need to create a simplified version of the Eclipse install directory. This directory has to contain the native launcher program, config files,and all the plug-ins required by the product. Thankfully, we've given the PDE enough information that it can put all this together for us now.In the Exporting section of the Product Configuration editor, click the link to Use the Eclipse Product export wizard. Set the root directory to something like RcpTutorial1. Then select the option to deploy into a Directory, and enter a directory path to a temporary (scratch) area such as C:\Deploy. Check the option to Include source code if you're building an open source project. Press Finish to build and export the program.The compiler options for source and class compatibility in the Eclipse Product export wizard will override any options you have specified on your project or global preferences. As part of the Export process, the plug-in is code is recompiled by an Ant script using these options.The application is now ready to run outside Eclipse. When you're done you should have a structure that looks like this in your deployment directory:RcpTutorial1| .eclipseproduct| eclipse.exe| startup.jar+--- configuration| config.ini+--- pluginsmands_3.1.0.jarorg.eclipse.core.expressions_3.1.0.jarorg.eclipse.core.runtime_3.1.2.jarorg.eclipse.help_3.1.0.jarorg.eclipse.jface_3.1.1.jarorg.eclipse.osgi_3.1.2.jarorg.eclipse.swt.win32.win32.x86_3.1.2.jarorg.eclipse.swt_3.1.0.jarorg.eclipse.ui.tutorials.rcp.part1_1.0.0.jarorg.eclipse.ui.workbench_3.1.2.jarorg.eclipse.ui_3.1.2.jarNote that all the plug-ins are deployed as jar files. This is the recommended format starting in Eclipse 3.1. Among other things this saves disk space in the deployed application.Previous versions of this tutorial recommended using a batch file or shell script to invoke your RCP program. It turns out this is a bad idea because you will not be able to fully brand your application later on. For example, you won't be able to add a splash screen. Besides, theexport wizard does not support the batch file approach so just stick with the native launcher.Give it a try! Execute the native launcher (eclipse or eclipse.exe by default) outside Eclipse and watch the application come up. The name of the launcher is controlled by branding options in the product configuration.TroubleshootingError: Launching failed because the org.eclipse.osgi plug-in is not included...You can get this error when testing the product if you've forgotten to list the plug-ins that make up the product. In the Product Configuration editor, select the Configuration tab, and add all your plug-ins plus all the ones they require as instructed above.Compatibility and migrationIf you are migrating a plug-in from version 2.1 to version 3.1 there are number of issues covered in the on-line documentation that you need to be aware of. If you're making the smaller step from 3.0 to 3.1, the number of differences is much smaller. See the References section for more information.One word of advice: be careful not to duplicate any information in both plug-in.xml and MANIFEST.MF. Typically this would not occur unless you are converting an older plug-in that did not use MANIFEST.MF into one that does, and even then only if you are editing the files by hand instead of going through the PDE.ConclusionIn part 1 of this tutorial, we looked at what is necessary to create a bare-bones Rich Client application. The next part will delve into the classes created by the wizards such as the WorkbenchAdvisor class. All the sample code for this part may be found in the accompanying zip file.ReferencesRCP Tutorial Part 2RCP Tutorial Part 3Eclipse Rich Client PlatformRCP Browser example (project org.eclipse.ui.examples.rcp.browser)PDE Does Plug-insHow to Internationalize your Eclipse Plug-inNotes on the Eclipse Plug-in ArchitecturePlug-in Migration Guide: Migrating to 3.1 from 3.0Plug-in Migration Guide: Migrating to 3.0 from 2.1译文：Rich Client教程第一部分The Rich Client Platform (RCP)是一种创建Java应用程序的令人兴奋的新方法，可以和任何平台下的自带应用程序进行竞争。

计算机专业外文资料翻译

英文文献Object persistence and JavaBy Arsalan Saljoughy, , 05/01/97Object durability, or persistence, is the term you often hear used in conjunction with the issue of storing objects in databases. Persistence is expected to operate with transactional integrity, and as such it is subject to strict conditions. (See the Resources section of this article for more information on transaction processing.) In contrast, language services offered through standard language libraries and packages are often free from transactional constraints.As we'll see in this article, evidence suggests that simple Java persistence will likely stem from the language itself, while sophisticated database functionality will be offered by database vendors.No object is an islandIn the real world, you rarely find an object that lacks relations to other objects. Objects are components of object models. The issue of object durability transcends the issue of object model durability and distribution once we make the observation that objects are interconnected by virtue of their relations to one another.The relational approach to data storage tends to aggregate data by type. Rows in a table represent the physical aggregate of objects of the same type on disk. The relationships among objects are then represented by keys that are shared across many tables. Although through database organization, relational databases sometimes allow tables that are likely to be used together to be co-located (or clustered) in the same logical partition, such as a database segment, they have no mechanism to store object relationships in the database. Hence, in order to construct an object model, these relationships are constructed from the existing keys at run time in a process referred to as table joins. This is the same well-known property of the relational databases called data independence. Nearly all variants of object databases offer some mechanism to enhance the performance of a system that involves complex object relationships over traditional relational databases.To query or to navigate?In storing objects on disk, we are faced with the choice of co-locating related objects to better accommodate navigational access, or to store objects in table-like collections that aggregate objects by type to facilitate predicate-based access (queries), or both. The co-location of objects in persistent storage is an area where relational and object-oriented databases widely differ. The choice of the query language is another area of consideration. Structured Query Language (SQL) and extensions of it have provided relational systems with a predicate-basedaccess mechanism. Object Query Language (OQL) is an object variant of SQL, standardized by ODMG, but support for this language is currently scant. Polymorphic methods offer unprecedented elegance in constructing a semantic query for a collection of objects. For example, imagine a polymorphic behavior for acccount called isInGoodStanding. It may return the Boolean true for all accounts in good standing, and false otherwise. Now imagine the elegance of querying the collection of accounts, where inGoodStanding is implemented differently based on business rules, for all accounts in good standing. It may look something like:setOfGoodCustomers = setOfAccounts.query(account.inGoodStanding());While several of the existing object databases are capable of processing such a query style in C++ and Smalltalk, it is difficult for them to do so for larger (say, 500+ gigabytes) collections and more complex query expressions. Several of the relational database companies, such as Oracle and Informix, will soon offer other, SQL-based syntax to achieve the same result. Persistence and typeAn object-oriented language aficionado would say persistence and type are orthogonal properties of an object; that is, persistent and transient objects of the same type can be identical because one property should not influence the other. The alternative view holds that persistence is a behavior supported only by persistable objects and certain behaviors may apply only to persistent objects. The latter approach calls for methods that instruct persistable objects to store and retrieve themselves from persistent storage, while the former affords the application a seamless view of the entire object model -- often by extending the virtual memory system. Canonicalization and language independenceObjects of the same type in a language should be stored in persistent storage with the same layout, regardless of the order in which their interfaces appear. The processes of transforming an object layout to this common format are collectively known as canonicalization of object representation. In compiled languages with static typing (not Java) objects written in the same language, but compiled under different systems, should be identically represented in persistent storage.An extension of canonicalization addresses language-independent object representation. If objects can be represented in a language-independent fashion, it will be possible for different representations of the same object to share the same persistent storage.One mechanism to accomplish this task is to introduce an additional level of indirection through an interface definition language (IDL). Object database interfaces can be made through the IDL and the corresponding data structures. The downside of IDL style bindings is two fold: First, the extra level of indirection always requires an additional level of translation, which impacts the overall performance of the system; second, it limits use of database services that are unique to particular vendors and that might be valuable to application developers.A similar mechanism is to support object services through an extension of the SQL. Relational database vendors and smaller object/relational vendors are proponents of this approach; however, how successful these companies will be in shaping the framework for object storage remains to be seen.But the question remains: Is object persistence part of the object's behavior or is it an external service offered to objects via separate interfaces? How about collections of objects and methods for querying them? Relational, extended relational, and object/relational approaches tend to advocate a separation between language, while object databases -- and the Java language itself -- see persistence as intrinsic to the language:Native Java persistence via serializationObject serialization is the Java language-specific mechanism for the storage and retrieval of Java objects and primitives to streams. It is worthy to note that although commercial third-party libraries for serializing C++ objects have been around for some time, C++ has never offered a native mechanism for object serialization. Here's how to use Java's serialization: // Writing "foo" to a stream (for example, a file)// Step 1. Create an output stream// that is, create bucket to receive the bytesFileOutputStream out = new FileOutputStream("fooFile");// Step 2. Create ObjectOutputStream// that is, create a hose and put its head in the bucketObjectOutputStream os = new ObjectOutputStream(out)// Step 3. Write a string and an object to the stream// that is, let the stream flow into the bucketos.writeObject("foo");os.writeObject(new Foo());// Step 4. Flush the data to its destinationos.flush();The Writeobject method serializes foo and its transitive closure -- that is, all objects that can be referenced from foo within the graph. Within the stream only one copy of the serialized object exists. Other references to the objects are stored as object handles to save space and avoid circular references. The serialized object starts with the class followed by the fields of each class in the inheritance hierarchy.// Reading an object from a stream// Step 1. Create an input streamFileInputStream in = new FileInputStream("fooFile");// Step 2. Create an object input streamObjectInputStream ins = new ObjectInputStream(in);// Step 3. Got to know what you are readingString fooString = (String)ins.readObject();Foo foo = (Foo)s.readObject();Object serialization and securityBy default, serialization writes and reads non-static and non-transient fields from the stream. This characteristic can be used as a security mechanism by declaring fields that may not be serialized as private transient. If a class may not be serialized at all, writeObject and readObject methods should be implemented to throw NoAccessException.Persistence with transactional integrity: Introducing JDBCModeled after X/Open's SQL CLI (Client Level Interface) and Microsoft's ODBC abstractions, Java database connectivity (JDBC) aims to provide a database connectivity mechanism that is independent of the underlying database management system (DBMS).To become JDBC-compliant, drivers need to support at least the ANSI SQL-2 entry-level API, which gives third-party tool vendors and applications enough flexibility for database access.JDBC is designed to be consistent with the rest of the Java system. Vendors are encouraged to write an API that is more strongly typed than ODBC, which affords greater static type-checking at compile time.Here's a description of the most important JDBC interfaces:java.sql.Driver.Manager handles the loading of drivers and provides support for new database connections.java.sql.Connection represents a connection to a particular database.java.sql.Statement acts as a container for executing an SQL statement on a given connection.java.sql.ResultSet controls access to the result set.You can implement a JDBC driver in several ways. The simplest would be to build the driver as a bridge to ODBC. This approach is best suited for tools and applications that do not require high performance. A more extensible design would introduce an extra level of indirection to the DBMS server by providing a JDBC network driver that accesses the DBMS server through a published protocol. The most efficient driver, however, would directly access the DBMS proprietary API.Object databases and Java persistenceA number of ongoing projects in the industry offer Java persistence at the object level. However, as of this writing, Object Design's PSE (Persistent Storage Engine) and PSE Pro are the only fully Java-based, object-oriented database packages available (at least, that I am aware of). Check the Resources section for more information on PSE and PSE Pro.Java development has led to a departure from the traditional development paradigm for software vendors, most notably in the development process timeline. For example, PSE and PSE Pro are developed in a heterogeneous environment. And because there isn't a linking step in the development process, developers have been able to create various functional components independent of each other, which results in better, more reliable object-oriented code.PSE Pro has the ability to recover a corrupted database from an aborted transaction caused by system failure. The classes that are responsible for this added functionality are not present in the PSE release. No other differences exist between the two products. These products are what we call "dribbleware" -- software releases that enhance their functionality by plugging in new components. In the not-so-distant future, the concept of purchasing large, monolithic software would become a thing of the past. The new business environment in cyberspace, together with Java computing, enable users to purchase only those parts of the object model (object graph) they need, resulting in more compact end products.PSE works by post-processing and annotating class files after they have been created by the developer. From PSE's point of view, classes in an object graph are either persistent-capable or persistent-aware. Persistent-capable classes may persist themselves while persistent-aware classes can operate on persistent objects. This distinction is necessary because persistence may not be a desired behavior for certain classes. The class file post-processor makes the following modifications to classes:Modifies the class to inherit from odi.Persistent or odi.util.HashPersistent.Defines the initializeContents() method to load real values into hollow instances of your Persistent subclass. ObjectStore provides methods on the GenericObject class that retrieves each Field type.Be sure to call the correct methods for the fields in your persistent object. A separate method is available for obtaining each type of Field object. ObjectStore calls the initializeContents() method as needed. The method signature is:public void initializeContents(GenericObject genObj)Defines the flushContents() method to copy values from a modified instance (active persistent object) back to the database. ObjectStore provides methods on the GenericObject Be sure to call the correct methods for the fields in your persistent object. A separate method is available for setting each type of Field object. ObjectStore calls the flushContents() method as needed. The method signature is:public void flushContents(GenericObject genObj)Defines the clearContents() method to reset the values of an instance to the default values. This method must set all reference fields that referred to persistent objects to null. ObjectStore calls this method as needed. The method signature is:public void clearContents()Modifies the methods that reference non-static fields to call the Persistent.fetch() and Persistent.dirty() methods as needed. These methods must be called before the contents of persistent objects can be accessed or modified, respectively. While this step is not mandatory, it does provide a systematic way to ensure that the fetch() or dirty() method is called prior to accessing or updating object content.Defines a class that provides schema information about the persistence-capable class.All these steps can be completed either manually or automatically.PSE's transaction semanticYou old-time users of ObjectStore probably will find the database and transaction semantics familiar. There is a system-wide ObjectStore object that initializes the environment and is responsible for system-wide parameters. The Database class offers methods (such as create, open, and close), and the Transaction class has methods to begin, abort, or commit transactions. As with serialization, you need to find an entry point into the object graph. The getRoot and setRoot methods of the Database class serve this function. I think a few examples would be helpful here. This first snippet shows how to initialize ObjectStore:ObjectStore.initialize(serverName, null);try {db = Database.open(dbName, Database.openUpdate);} catch(DatabaseNotFoundException exception) {db = Database.create(dbName, 0664);}This next snippet shows how to start and commit a transaction:Transaction transaction = Transaction.begin(Transaction.update);try {foo = (Foo)db.getRoot("fooHead");} catch(DatabaseRootNotFoundException exception) {db.createRoot("fooHead", new Foo());}mit();The three classes specified above -- Transaction, Database, and ObjectStore -- are fundamental classes for ObjectStore. PSE 1.0 does not support nested transactions, backup and recovery, clustering, large databases, object security beyond what is available in the language, and any type of distribution. What is exciting, however, is all of this functionality will be incrementally added to the same foundation as the product matures.About the authorArsalan Saljoughy is asystems engineer specializing in object technology at Sun Microsystems. He earned his M.S. in mathematics from SUNY at Albany, and subsequently was a research fellow at the University of Berlin. Before joining Sun, he worked as a developer and as an IT consultant to financial services companies.ConclusionAlthough it is still too early to establish which methodology for object persistence in general and Java persistence in particular will be dominant in the future, it is safe to assume that a myriad of such styles will co-exist. The shift of storing objects as objects without disassembly into rows and columns is sure to be slow, but it will happen. In the meantime, we are more likely to see object databases better utilized in advanced engineering and telecommunications applications than in banking and back-office financial applications.英文翻译对象持久化和Java－深入的了解面向对象语言中的对象持久的讨论Arsalan Saljoughy,, 05/01/97对象持久化这个术语你常常会和数据存储一起听到。

外文文献—计算机网络

英文原文：Computer networkA computer network, often simply referred to as a network, is a collection of computers and devices interconnected by communications channels that facilitate communications among users and allows users to share resources. Networks may be classified according to a wide variety of characteristics. A computer network allows sharing of resources and information among interconnected devices.History ：Early networks of communicating computers included the military radar system Semi-Automatic Ground Environment (SAGE) and its relative the commercial airline reservation system Semi-Automatic Business Research Environment (SABRE),started in the late 1950s.[1][2]When Russia launched His SPUTNIK Satellite in Space In 1957.The American Started Agency Names ADV ANCE RESEARCH PROJECT AGENCY (ARPA) & launched THis 1st Satellite Within 18 Month After Establishment.Then Sharing Of TheInformation InAnother Computer They Use ARPANET.And This All Responsibility On America's Dr.LIED LIEDER.Then in 1969,ARPANET Comes in INDIA And INDIAN Switched This Name To NETWORK. In the 1960s, the Advanced Research Projects Agency (ARPA) started funding the design of the Advanced Research Projects Agency Network (ARPANET) for the United States Department of Defense. Development of the network began in 1969, based on designs developed during the1960s.[3] The ARPANET evolved into the modern Internet.Purpose ：Computer networks can be used for a variety of purposes: Facilitating communications. Using a network, people can communicate efficiently and easily via email, instant messaging, chat rooms, telephone, video telephone calls, and video conferencing.Sharing hardware.：In a networked environment, each computer on a network may access and use hardware resources on the network, such as printing a document on a shared network printer.Sharing files, data, and information. In a network environment, authorized user may access data and information stored on other computers on the network. The capability of providing access to data and information on shared storage devices is an important feature of many networks.Sharing software.：Users connected to a network may run application programs on remote computers.information preservationSecurityNetwork classification The following list presents categories used for classifying networks.Connection method ：Computer networks can be classified according to thehardware and software technology that is used to interconnect the individual devices in the network, such as optical fiber, Ethernet, wireless LAN, HomePNA, power line communication or G.hn.Ethernet as it is defined by IEEE 802 utilizes various standards and mediums that enable communication between devices. Frequently deployed devices include hubs, switches, bridges, or routers. Wireless LAN technology is designed to connect devices without wiring. These devices use radio waves or infrared signals as a transmission medium. ITU-T G.hn technology uses existing home wiring (coaxial cable, phone lines and power lines) to create a high-speed (up to 1 Gigabit/s) local area network.Wired technologies ：Twisted pair wire is the most widely used medium for telecommunication.Twisted-pair cabling consist of copper wires that are twisted into pairs. Ordinary telephone wires consist of two insulated copper wires twisted into pairs. Computer networking cabling consist of 4 pairs of copper cabling that can be utilized for both voice and data transmission. The use of two wires twisted together helps to reduce crosstalk and electromagnetic induction. The transmission speed ranges from 2 million bits per second to 100 million bits per second. Twisted pair cabling comes in two forms which are Unshielded Twisted Pair (UTP) and Shielded twisted-pair (STP) which are rated in categories which are manufactured in different increments for various scenarios.Coaxial cable is widely used for cable television systems, office buildings, and other work-sites for local area networks. The cables consist of copper or aluminum wire wrapped with insulating layer typically of a flexible material with a high dielectric constant, all of which are surrounded by a conductive layer. The layers of insulation help minimize interference and distortion. Transmissionspeed range from 200 million to more than 500 million bits per second.Optical fiber cable consists of one or more filaments of glass fiber wrapped in protective layers. It transmits light which can travel over extended distances.Fiber-optic cables are not affected by electromagnetic radiation. Transmission speedmay reach trillions of bits per second. The transmission speed of fiber optics is hundreds of times faster than for coaxial cables and thousands of times faster than atwisted-pair wire.[citation needed]Wireless technologies ：Terrestrial microwave – Terrestrial microwaves use Earth-based transmitter and receiver. The equipment looks similar to satellite dishes. Terrestrial microwaves use low-gigahertz range, which limits all communications to line-of-sight. Path between relay stations spaced approx, 30 miles apart. Microwave antennas are usually placed on top of buildings, towers, hills, and mountain peaks.Communications satellites –The satellites use microwave radio as their telecommunications medium which are not deflected by the Earth's atmosphere. The satellites are stationed in space, typically 22,000 miles (for geosynchronous satellites) above the equator. These Earth-orbiting systems are capable of receiving and relayingvoice, data, and TV signals.Cellular and PCS systems – Use several radio communications technologies. The systems are divided to different geographic areas. Each area has a low-power transmitter or radio relay antenna device to relay calls from one area to the next area.Wireless LANs –Wireless local area network use a high-frequency radio technology similar to digital cellular and a low-frequency radio technology. Wireless LANs use spread spectrum technology to enable communication between multiple devices in a limited area. An example of open-standards wireless radio-wave technology is IEEE.Infrared communication , which can transmit signals between devices within small distances not more than 10 meters peer to peer or ( face to face ) without any body in the line of transmitting.Scale：Networks are often classified as local area network (LAN), wide area network (WAN), metropolitan area network (MAN), personal area network (PAN), virtual private network (VPN), campus area network (CAN), storage area network (SAN), and others, depending on their scale, scope and purpose, e.g., controller area network (CAN) usage, trust level, and access right often differ between these types of networks. LANs tend to be designed for internal use by an organization's internal systems and employees in individual physical locations, such as a building, while WANs may connect physically separate parts of an organization and may include connections to third parties.Functional relationship (network architecture) ：Computer networks may be classified according to the functional relationships which exist amongthe elements of the network,e.g., active networking, client–server, Wireless ad hoc network andpeer-to-peer (workgroup) architecture.Network topology ：Main article: Network topology Computer networks may be classified according to the network topology upon which the network is based, such as bus network, star network, ring network, mesh network.Network topology is the coordination by which devices in the network are arranged in their logical relations to one another, independent of physical arrangement. Even if networked computers are physically placed in a linear arrangement and are connected to a hub, the network has a star topology, rather than a bus topology. In this regard the visual and operational characteristics of a network are distinct. Networks may be classified based on the method of data used to convey the data, these include digital and analog networks.Types of networks based on physical scopeCommon types of computer networks may be identified by their scale.Local area network：A local area network (LAN) is a network that connects computers and devices in a limited geographical area such as home, school, computer laboratory, office building, or closely positioned group of buildings. Each computer or device on the network is a node. Current wired LANs are most likely to be based on Ethernettechnology, although new standards like ITU-T G.hn also provide a way to create a wired LAN using existing home wires (coaxial cables, phone lines and power lines).[4]Typical library network, in a branching tree topology and controlled access to resources All interconnected devices must understand the network layer (layer 3), because they are handling multiple subnets (the different colors). Those inside the library, which have only 10/100 Mbit/s Ethernet connections to the user device and a Gigabit Ethernet connection to the central router, could be called "layer 3 switches" because they only have Ethernet interfaces and must understand IP. It would be more correct to call them access routers, where the router at the top is a distribution router thatconnects to the Internet and academic networks' customer access routers.The defining characteristics of LANs, in contrast to WANs (Wide Area Networks), include their higher data transfer rates, smaller geographic range, and no need for leased telecommunication lines. Current Ethernet or other IEEE 802.3 LAN technologies operate at speeds up to 10 Gbit/s. This is the data transfer rate. IEEE has projects investigating the standardization of 40 and 100 Gbit/s.[5]Personal area network :A personal area network (PAN) is a computer network used for communication among computer and different information technological devices close to one person. Some examples of devices that are used in a PAN are personal computers, printers, fax machines, telephones, PDAs, scanners, and even video game consoles. A PAN may include wired and wireless devices. The reach of a PAN typically extends to 10 meters.[6] A wired PAN is usually constructed with USB and Firewire connections while technologies such as Bluetooth and infrared communication typically form a wireless PAN.Home area network :A home area network (HAN) is a residential LAN which is used for communication between digital devices typically deployed in the home, usually a small number of personal computers and accessories, such as printers and mobile computing devices. An important function is the sharing of Internet access, often a broadband service through a CATV or Digital Subscriber Line (DSL) provider. It can also be referred to as an office area network (OAN).Wide area network :A wide area network (WAN) is a computer network that covers a large geographic area such as a city, country, or spans even intercontinental distances, using a communications channel that combines many types of media such as telephone lines, cables, and air waves. A WAN often uses transmission facilities provided by common carriers, such as telephone companies. WAN technologies generally function at the lower three layers of the OSI reference model: the physical layer, the data link layer, and the network layer.Campus network :A campus network is a computer network made up of an interconnection of local area networks (LAN's) within a limited geographical area. The networkingequipments (switches, routers) and transmission media (optical fiber, copper plant, Cat5 cabling are almost entirely owned (by the campus tenant / owner: an enterprise, university, government etc.).In the case of a university campus-based campus network, the network is likely to link a variety of campus buildings including; academic departments, the university library and student residence halls.Metropolitan area network:A Metropolitan area network is a large computer network that usually spans a city or alarge campus. Sample EPN made of Frame relay WAN connections and dialup remote access.Enterprise private network :An enterprise private network is a network build by an enterprise to interconnect various company sites, e.g., production sites, head offices, remote offices, shops, in order to share computer resources.Virtual private network :A virtual private network (VPN) is a computer network in which some of the links between nodes are carried by open connections or virtual circuits in some larger network (e.g., the Internet) instead of by physical wires. The data link layer protocols of the virtual network are said to be tunneled through thelarger network when this is the case. One common application is secure communications through the public Internet, but a VPN need not have explicit security features, such as authentication or content encryption. VPNs, for example, can be used to separate the traffic of different user communities over an underlying network with strong security features.VPN may have best-effort performance, or may have a defined service level agreement (SLA) between the VPN customer and the VPN service provider. Generally, a VPN has a topology more complex than point-to-point.Internetwork :An internetwork is the connection of two or more private computer networks via a common routing technology (OSI Layer 3) using routers. The Internet is an aggregation of many internetworks, hence its name was shortened to Internet.Backbone network :A Backbone network (BBN) A backbone network or network backbone is part of a computer network infrastructure that interconnects various pieces of network, providing a path for the exchange of information between different LANs or subnetworks.[1][2] A backbone can tie together diverse networks in the same building, in different buildings in a campus environment, or over wide areas. Normally, the backbone's capacity is greater than the networks connected to it.A large corporation that has many locations may have a backbone network that ties all of the locations together, for example, if a server cluster needs to be accessed by different departments of a company that are located at different geographical locations.The pieces of the network connections (for example: ethernet, wireless) that bring these departments together is often mentioned as network backbone. Networkcongestion is often taken into consideration while designing backbones. Backbone networks should not be confused with the Internet backbone.Global area network:A global area network (GAN) is a network used for supporting mobile communications across an arbitrary number of wireless LANs, satellite coverage areas, etc. The key challenge in mobile communications is handing off the user communications from one local coverage area to the next. In IEEE Project 802, this involves a succession of terrestrial wireless LANs.[7]Internet :The Internet is a global system of interconnected governmental, academic, corporate, public, and private computer networks. It is based on the networking technologies of the Internet Protocol Suite. It is the successor of the Advanced Research ProjectsAgency Network (ARPANET) developed by DARPA of the United States Department of Defense. The Internet is also the communications backbone underlying the World Wide Web (WWW).Intranets and extranets :Intranets and extranets are parts or extensions of a computer network, usually a local area network. An intranet is a set of networks, using the Internet Protocol and IP-based tools such as web browsers and file transfer applications, that is under the control of a single administrative entity. That administrative entity closes the intranet to all but specific, authorized users. Most commonly, an intranet is the internal network of an organization. A large intranet will typically have at least one web server to provide users with organizational information.An extranet is a network that is limited in scope to a single organization or entity and also has limited connections to the networks of one or more other usually, but not necessarily, trusted organizations or entities—a company's customers may be given access to some part of its intranet—while at the same time the customers may not be considered trusted from a security standpoint. Technically, an extranet may also be categorized as a CAN, MAN, WAN, or other type of network, although an extranet cannot consist of a single LAN; it must have at least one connection with an external network.Overlay network:An overlay network is a virtual computer network that is built on top of another network. Nodes in the overlay are connected by virtual or logical links, each of which corresponds to a path, perhaps through many physical links, in the underlying network.中文译文：计算机网络计算机网络，通常简单的被称作是一种网络，是一家集电脑和设备为一体的沟通渠道，便于用户之间的沟通交流和资源共享。

Internet中英文资料对照外文翻译文献综述

中英文资料对照外文翻译文献综述Internet的历史起源——ARPAnetInternet是被美国政府作为一项工程进行开发的。

这项工程的目的，是为了建立远距离之间点与点的通信，以便处理国家军事范围内的紧急事件，例如核战争。

这项工程被命名为ARPAnet，它就是Internet的前身。

建立此工程的主要应用对象就是军事通讯，那些负责ARPAnet的工程师们当时也没有想到它将成为“Internet”。

根据定义，一个“Internet”应该由四或者更多的计算机连接起来的网络。

ARPAnet是通过一种叫TCP/IP的协议实现连网工作的。

此协议最基础的工作原理是：如果信息在网络中的一条路径发送失败，那么它将找到其他路径进行发送，就好象建立一种语言以便一台计算机与其他计算机“交谈”一样，但不注意它是PC，或是Macintosh。

到了20世纪80年代，ARPAnet已经开始变成目前更为有名的Internet了，它拥有200台在线主机。

国防部很满意ARPAnets的成果，于是决定全力将它培养为能够联系很多军事主机，资源共享的服务网络。

到了1984年，它就已经超过1000台主机在线了。

在1986年ARPAnet关闭了，但仅仅是建立它的机构关闭了，而网络继续存在与超过1000台的主机之间。

由于使用NSF连接失败，ARPAnet才被关闭。

NSF是将5个国家范围内的超级计算机连入ARPAnet。

随着NSF的建立，新的高速的传输介质被成功的使用，在1988年，用户能通过56k的电话线上网。

在那个时候有28，174台主机连入Internet。

到了1989年有80，000台主机连入Internet。

到1989年末，就有290，000台主机连入了。

另外还有其他网络被建立，并支持用户以惊人的数量接入。

于1992年正式建立。

现状——Internet如今，Internet已经成为人类历史上最先进技术的一种。

每个人都想“上网”去体验一下Internet中的信息财富。

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New technique of the computer networkAbstractThe 21 century is an ages of the information economy, being the computer network technique of representative techniques this ages, will be at very fast speed develop soon in continuously creatively, and will go deep into the people's work, life and study. Therefore, control this technique and then seem to be more to deliver the importance. Now I mainly introduce the new technique of a few networks in actuality live of application.keywordsInternet Network System Digital Certificates Grid Storage1. ForewordInternet turns 36, still a work in progressThirty-six years after computer scientists at UCLA linked two bulky computers using a 15-foot gray cable, testing a new way for exchanging data over networks, what would ultimately become the Internet remains a work in progress.University researchers are experimenting with ways to increase its capacity and speed. Programmers are trying to imbue Web pages with intelligence. And work is underway to re-engineer the network to reduce Spam (junk mail) and security troubles.All the while threats loom: Critics warn that commercial, legal and political pressures could hinder the types of innovations that made the Internet what it is today.Stephen Crocker and Vinton Cerf were among the graduate students who joined UCLA professor Len Klein rock in an engineering lab on Sept. 2, 1969, as bits of meaningless test data flowed silently between the two computers. By January, three other "nodes" joined the fledgling network.Then came e-mail a few years later, a core communications protocol called TCP/IP in the late 70s, the domain name system in the 80s and the World Wide Web - now the second most popular application behind e-mail - in 1990. The Internet expanded beyond its initial military and educational domain into businesses and homes around the world.Today, Crocker continues work on the Internet, designing better tools for collaboration. And as security chairman for the Internet's key oversight body, he is trying to defend the core addressing system from outside threats.He acknowledges the Internet he helped build is far from finished, and changes are in store to meet growing demands for multimedia. Network providers now make only "best efforts" at delivering data packets, and Crocker said better guarantees are needed to prevent the skips and stutters now common with video.Cerf, now at MCI Inc., said he wished he could have designed the Internet with security built-in. Microsoft Corp.Yahoo Inc. and America Online Inc., among others, are currently trying to retrofit the network so e-mail senders can be authenticated - a way to cut down on junk messages sent using spoofed addresses.Many features being developed today wouldn't have been possible at birth given the slower computing speeds and narrower Internet pipes, or bandwidth, Cerf said.2.Digital CertificatesDigital certificates are data files used to establish the identity of people and electronic assets on the Internet. They allow for secure, encrypted online communication and are often used to protect online transactions.Digital certificates are issued by a trusted third party known as a certification authority (CA). The CA validates the identity of a certificate holder and “signs” the certificate to a ttest that it hasn’t been forged or altered in any way.New Uses For Digital CertificatesDigital certificates are now being used to provide security and validation for wireless connections, and hardware manufacturers are one of the latest groups to use them. Not long ago, Version Inc. announced its Cable Modem Authentication Services, which allow hardware manufacturers to embed digital certificates into cable modems to help prevent the pirating of broadband services through device cloning.Using Version software, hardware makers can generate cryptographic keys and corresponding digital certificates those manufacturers or cable service providers can use to automatically identify individual modems.This ‘ast-mile’authentication not only protects the value of existing content and services but also positions cable system operators to bring a broad new range of content, applications and value-added services to market.When a CA digitally signs a certificate, its owner can use it as an electronic passport to prove his identity. It can be presented to Web sites, networks or individuals that require secure access.Identifying information embedded in the certificate includes the holder’ s name and e-mail address, the name of the CA, a serial number and any activation or expiration data for the certificate. When the CA verifies a user’s identity, the certificate uses the holder’s public encryption key to protect this data.Certificates that a Web server uses to confirm the authenticity of a Web site for a user’s browser also employ public keys. When a user wants to send confidential information to a Web server, such as a credit-card number for an online transaction, the browser will access the public key in the server’s digital certificate to verify its identity.Role of Public-Key CryptographyThe public key is one half of a pair of keys used in public-key cryptography, which provides the foundation for digital certificates.Public-key cryptography uses matched public and private keys for encryption and decrypt ion. These keys have a numerical value that’s used by an algorithm to scramble information and make it readable only to users with the corresponding decryption key.Others to encrypt information meant only for that person use a person’s public key. When he receives the information, he uses his corresponding private key, which is kept secret, to decrypt the data. A person's public key can be distributed without damaging the private key. A Web server using a digital certificate can use its private key to make sure that only it can decrypt confidential information sent to it over the Internet.The Web server’s certificate is validated by a self-signed CA certificate that identifies the issuing CA. CA certificates are preinstalled on most major Web browsers, including Microsoft Internet Explorer and Netscape Navigator.The CA certificate tells users whether they can trust the Web server certificate when it’s presented to the browser. If the validity of the Web server certificate is affirmed, the certificate’s public key is used to secure information for the server using Secure Sockets Layer (SSL) technology.Digital certificates are used by the SSL security protocol to create a secure “pipe” between two parties that seek confidential communication. SSL is used in most major Web browsers and commercial Web servers.3. Digital Wallets----A digital wallet is software that enables users to pay for goods on the Web ．It holds credit-card numbers and other personal information such as a shipping address ．Once entered，the data automatically populates order fields at merchant sites ．----When using a digital wallet，consumers don’t need to fill out order forms on each site when they purchase an item because the information has already been stored and is automatically updated and entered into the order fields across merchant sites ．Consumers also benefit when using digital wallets because their information is encrypted or protected by a private software code ．And merchants benefit by receiving protection against fraud ．----Digital wallets are available to consumers free of charge，and they’re fairly easy to obtain ．For example，when a consumer makes a purchase at a merchant site that’s set up to handle server-side digital wallets，he types his name and payment and shipping information into the merchant’s own form ．At the end of the purchase，one consumer is asked to sign up for a wallet of his choice by entering a user name and password for future purchases ．Users can also acquire wallets at a wallet vendor’s site ．----Although a wallet is free for consumers，vendors charge merchants for wallets ．----Digital wallets come in two main types: client-side and server- side ．Within those divisions are wallets that work only on specific merchant sites and those that are merchant agnostic ．----Client-based digital wallets，the older of the two types，are falling by the wayside，according to analysts，because they require users to download and install software ．A user downloads the wallet application and inputs payment and mailinginformation ．At that point，the information is secured and encrypted on the user’s hard drive ．The user retains control of his credit card and personal information locally ．----With a server-based wallet，a user fills out his personal information，and a cookie is automatically downloaded ．(A cookie is a text contains information about the user ．）In this scenario，the consumer information resides on the server of a financial institution or a digital wallet vendor rather than on the user’s PC ．----Server-side wallets provide assurance against merchant fraud because they use certificates to verify the identity of all parties ．When a party makes a transaction，it presents its certificate to the other parties involved ．A certificate is an attachment to an electronic message used to verify the identity of the party and to provide the receiver with the means to encode a reply ．----Furthermore，the cardholder’s sensitive data is typically housed at a financial institution，so there’s an extra sense of security because financial environments generally provide the highest degree of security ．----But even though wallets provide easy shopping online，adoption hasn’t been widespread ．----Standards are pivotal to the success of digital wallets ．----Last month，major vendors，including Microsoft Corp ．，Sun Microsystems Inc ．and America Online Inc ．announced their endorsement of a new standard called EMCL，or E-Commerce Modeling Language，to give Web merchants a standardized way to collect electronic data for shipping，billing and payment ．4. Grid StorageDefinition: Grid storage, analogous to grid computing, is a new model for deploying and managing storage distributed across multiple systems and networks, making efficient use of available storage capacity without requiring a large, centralized switching system.A grid is, in fact, a meshed network in which no single centralized switch or hub controls routing. Grids offer almost unlimited scalability in size and performance because they aren’t constrained by the need for ev er-larger central switches. Grid networks thus reduce component costs and produce a reliable and resilient structure.Applying the grid concept to a computer network lets us harness available but unused resources by dynamically allocating and deal locating capacity, bandwidth and processing among numerous distributed computers. A computing grid can span locations, organizations, machine architectures and software boundaries, offering power, collaboration and information access to connected users. Universities and research facilities are using grids to build what amounts to supercomputer capability from PCs, Macintoshes and Linux boxes.After grid computing came into being, it was only a matter of time before a similar model would emerge for making use of distributed data storage. Most storage networks are built in star configurations, where all servers and storage devices are connected to a single central switch. In contrast, grid topology is built with a network of interconnected smaller switches that can scale as bandwidth increases and continue to deliver improved reliability and higher performance and connectivity.Based on current and proposed products, it appears that a grid storage system should include the following:Modular storage arrays: These systems are connected across a storage network using serial ATA disks. The systems can be block-oriented storage arrays or network-attached storage gateways and servers.Common virtualization layer: Storage must be organized as a single logical pool of resources available to users.Data redundancy and availability: Multiple copies of data should exist across nodes in the grid, creating redundant data access and availability in case of a component failure.Common management: A single level of management across all nodes should cover the areas of data security, mobility and migration, capacity on demand, and provisioning.Simplified platform/management architecture: Because common management is so important, the tasks involved in administration should be organized in modular fashion, allowing the auto discovery of new nodes in the grid and automating volume and .Three Basic BenefitsApplying grid topology to a storage network provides several benefits, including the following:Reliability. A well-designed grid network is extremely resilient. Rather than providing just two paths between any two nodes, the grid offers multiple paths between each storage node. This makes it easy to service and replace components in case of failure, with minimal impact on system availability or downtime.Performance. The same factors that lead to reliability also can improve performance. Not requiring a centralized switch with many ports eliminates a potential performance bottleneck, and applying load-balancing techniques to the multiple paths available offers consistent performance for the entire network.Scalability. It’s easy to expand a grid network using inexpensive switches with low port counts to accommodate additional servers for increased performance, bandwidth and capacity. In essence, grid storage is a way to scale out rather than up, using relatively inexpensive storage building blocks.计算机网络摘要：21世纪是信息经济的时代，作为这个时代的代表技术，计算机网络技术将在非常快的速度发展很快，不断创造性地将进入人们的工作，学习和生活中深。