Multiple Transports and Serial Communications

It is possible to configure several transports to carry one endpoint ability. In such cases, communications are serial.

For example, connectors could specify that a multicast transport and a TCP transport both carry the send ability. The multicast transport reaches receivers within a LAN, and the TCP transport reaches remote receivers. (In this example, no intervening hardware router exists to forward multicast packets.)

When two or more transports carry an endpoint ability, the TIBCO FTL base library arranges their communications serially, within one thread, according to the order that the transports appear in the application instance’s endpoint connectors.

Serial communications apply in two situations:

• Send abilities place outbound message data from a send call on each transport serially.
• Receive abilities associated with inline event queues accomplish all six phases of delivery in a single thread, attending to each transport in a round-robin arrangement. For background information, see Inline Mode for Administrators.

  (In contrast, receive abilities associated with regular event queues receive inbound messages from several transports in separate threads. The dispatch phase merges them into the event queue for dispatch in yet another thread.)