Tibco不可多得的内部培训资料

TIBCO‘s information bus (TIB)一、introduction

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Examples of Valid Subject Names:

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1. NEWS.NATIONAL.ARTS.MOVIES.REVIEWS

2. CHAT.DEVELOPMENT.BIG_PROJECT.DESIGN

3. News.Sports.Baseball

4. finance

5. Long.subject_name.is.valid.even.though.quite.uninformative

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Examples of INVALID Subject Names:

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News..Natural_Disasters.Flood

- Invalid null element in subject string

WRONG.

- Invalid null element at the end of the subject string

.TRIPLE.WRONG..

Invalid subject string with three null elements

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Reserved Names

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_INBOX.

- Inboxes are subject names used for point-to-point message delivery

- All system generated inbox names begin with this prefix

_LOCAL.

- Subject names with this prefix are ―local‖to the TIBCO Rendezvous daemon

- These messages do not reach the network

_RV.

- Subject names with this prefix are TIBCO Rendezvous advisory messages

_RVCM.

- Subject names with this prefix indicate internal administrative messages associated with certified message delivery

- Application programs must not send to subjects with this prefix

_RVFT.

- Subject names with this prefix indicate internal administrative messages associated with TIBCO Rendezvous fault tolerance software

- Application programs must not send to subjects with this prefix

Publish/subscribe messages are like radio broadcasts; the sender picks a frequency, and any listener who tunes to that frequency receives the broadcast. The broadcast subject name is analogous to a radio frequency. Any application that listens for a subject receives all messages bearing that subject name.

The Rendezvous Daemon (rvd) is a runtime background process that implements TIBCO Reliable Datagram Protocol (TRDP). The daemon sends, listens for, filters and routes subject-based messages reliably, detects lost messages and requests re-transmission. Daemons can be started automatically or manually.

The Rendezvous API supplies the message structure and communication type and passes messages to the daemon via a TCP connection. Usually a Rendezvous daemon is run on the same machine as the Rendezvous application but remote daemon connections are possible.

In the above slide the various layers of the stack

pass up traffic, but only if a higher layer has

registered interest in some manner.

The Network Interface Card (NIC) will only

process network traffic which meets one of three

criteria:

- Own hardware address

- Broadcast

- Address contained on Multicast table

The NIC Driver will process and forward traffic

which is registered at the TCP/IP layer

The TCP/IP layer will only forward traffic which is routed to an open TCP/UDP port, e.g. 7500/UDP default for the TIBCO Rendezvous daemon

The TIBCO Rendezvous daemon will only forward traffic on which a connected consumer application has registered subject interest, and only after the complete message has been received

TRDP is implemented by the TIBCO Rendezvous

each outbound message packet. TRDP uses a

buffer to store outbound messages for a specified

interval. If a message packet is lost the consuming

rvd requests retransmission. Buffer operations are

private to the TRDP implementation; there is no

API to access it.

TRDP is optimistic: it assumes messages will arrive

at their destination. Only if a message is lost will

TRDP send a negative acknowledgement (NAK)

requesting retransmission. Compare this with TCP which is pessimistic: explicit acknowledgment of each received message is required.

The default buffer interval is 60 seconds and should not be increased. If stronger delivery assurance is required, Rendezvous certified (RVCM) messaging should be used

TIBCO Rendezvous Certified Messaging

While standard Rendezvous communication is highly reliable, business requirements often dictate the need for even stronger assurance of message delivery. RVCM fulfills this need, guaranteeing the delivery

of each message at its intended destination.