UNIX® System V Network Programming

4. The Transport Layer Interface

The Transport Layer Interface (TLI) is the primary networking interface used in UNIX System V. It is accessed at user level through a library and at kernel level through a STREAMS message-based service interface. This chapter will present the transport interface as user-level applications view it.

4.1. Introduction

The Transport Layer Interface presents a generic view of a network, corresponding to the transport level in the OSI seven-layer model of a network (see Figure 4.1).

Fig. 4.1. The OSI Model

The TLI was first provided in UNIX System V Release 3.0. A transport-level interface was chosen for two reasons. ...