Page 31-1

31 WAN Links

Introduction
This chapter describes the procedures for configuring a “WAN link” between an already
created PPP Entity (see Chapter 30, Point-to-Point Protocol) and the physical interface that
will be used to carry PPP traffic. The procedures described in this chapter comprise the third
and final step in the three-step process for configuring the operation of PPP on your Omni
Switch/Router (the complete three-step process was also described in Chapter 30).
Here is a brief review of the PPP configuration process: the first step is to configure the physi-
cal interfaces that will carry PPP traffic. The second step is to configure the operation of PPP
itself by creating “PPP Entities.” The third step is to configure the “link” between an existing
PPP Entity and the physical interface that will be used to carry PPP traffic (hence the name
“WAN Links”).

Configuring WAN Interfaces

Three kinds of physical WAN interfaces can support PPP connections: serial ports (WSX-S),
T1/E1 channels (WSX-FT1/E1), and ISDN lines (WSX-BRI). The “WAN Links” you create to
support PPP connections vary somewhat, depending upon the type of physical interface
being used. When the physical interface being used is a Universal Serial Port (USP) or a frac-
tional T1/E1 channel (which are permanent channels), the port is dedicated to the PPP
connection and the “WAN Link” simply identifies the physical interface in terms of the slot
and port. When the physical interface being used is an ISDN interface (which provides
dynamic, switched connections), the “WAN Link” identifies the numbering information that is
to be used to establish the serial connection and the slot/port if necessary.
Related Hardware Chapters
The configuration of an ISDN interface is described in
Chapter 32, Managing ISDN Ports. The configuration of
a T1/E1 interface is described in Chapter 33, Manag-
ing T1 and E1 Ports. The configuration of a universal
serial port (USP) on a WSX-S board is described in
Chapter 28, Managing WAN Switching Modules. The
ISDN WSX board (WSX-BRI) also contains a USP; this
port on the WSX-BRI board may be configured in a
similar manner to the USP ports on the WSX-S board.