Transport Layer Interface

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The Transport Layer Interface (TLI) is an API in network programming that makes the services of the transport layer available to application programs . It offers functionality similar to sockets , but is more closely based on the OSI reference model .

TLI was introduced in AT&T UNIX System V Release 3.0 as an alternative to BSD sockets and implemented in SVR4 with the help of streams. The XTI of the X / Open Group is based on the TLI. At that time it was assumed that the OSI protocols would replace TCP / IP.

In fact, neither TLI nor XTI ever experienced the prevalence of BSD sockets. Although some operating systems still support TLI, sockets have become the de facto standard in network programming today.


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