Network services

Network selection

In order for network applications to be portable to different environments, the application process must have a standard interface into the various transport providers available in any current environment. Network selection provides a simple and consistent interface that allows user applications to select networks (at the transport level), enabling applications to be protocol- and media-independent. System V Networking Services applications that allow the user to influence the choice of transports use the standard interface outlined here.

Network selection routines may be employed by the client portion of an application when the application initiates communication with its peer application on another machine; they may also be used by the server portion of an application when it offers its service. On a machine connected to a single network, network selection makes it possible for the application to make use of that network without requiring application-specific action by the administrator or user. On a machine connected to multiple networks, network selection makes it easy for the application to try each alternative network in turn, until it succeeds in establishing communication, and to try them either in the order specified as the local default sequence established by the system administrator or in the order preferred by the user. It also allows server-side applications to accept requests over multiple networks.

Choosing among the available networks is the responsibility of the application. The network selection mechanism is intended to make that selection uniform and simple.

© 2004 The SCO Group, Inc. All rights reserved.
UnixWare 7 Release 7.1.4 - 27 April 2004