The interfaces that are described in this chapter are multithread safe. “Multithread safe” means that you can use applications that contain transport selection interface calls freely in a multithreaded application. These interface calls do not provide linear scalability because the calls are not re-entrant.
A distributed application must use a standard interface to the transport services to be portable to different protocols. Transport selection services provide an interface that allows an application to select which protocols to use. This interface makes an application independent of protocol and medium.
Transport selection means that a client application can easily try each available transport until the client establishes communication with a server. Transport selection enables request acceptance on multiple transports by server applications. The applications can then communicate over a number of protocols. Transports can be tried in either the order specified by the local default sequence or in an order specified by the user.
Choosing from the available transports is the responsibility of the application. The transport selection mechanism makes that selection uniform and simple.