User`s guide

Configuring IP Routing
Introduction to IP routing on the Pipeline
2-12 Preliminary January 30, 1998 Pipeline User’s Guide
Specifying the remote interface address
This section provides some guidelines on using interface-based routing.
If both the system and interface addresses are known
If you are adding interface-based routing to a system set up for system-based
routing, enter the remote interface address in the WAN Alias parameter of the
Connection profile. WAN Alias identifies the remote end of the link. If a WAN
Alias is set, the following processes occur:
• Host routes are created to LAN Adrs and WAN Alias, and the WAN Alias is
listed in the routing table as a gateway (next hop) to the Lan Adrs.
• A route is created to the remote system's subnet, showing the WAN Alias as
the next hop.
• Incoming PPP/MPP calls must report their IP addresses as the WAN Alias
(rather than the Lan Adrs). That is, the caller must be using a numbered
interface, and its interface address must agree with the WAN Alias on the
receiving side.
To create static routes to hosts at the remote end, use the WAN Alias address as
the “next hop” (gateway) field. (The Lan Adrs address will also work, as it is for
system-based routing.)
If only the interface address is known
You can omit the remote side’s system address from the profile and use interface-
based routing exclusively. This is an appropriate mechanism if, for example, the
remote system is on a backbone net which might be periodically reconfigured by
its administrators, and you want to refer to the remote system only by its
mutually agreed-upon interface address.
In this case, the remote interface address is entered in the Lan Adrs parameter,
and the WAN Alias is left as default (0.0.0.0). Note that Lan Adrs must always be
filled in, so if the only known address is the interface address, it must be placed in
the Lan Adrs parameter rather than the WAN Alias parameter.
If the remote interface address is placed in the Lan Adrs parameter, the following
will take place: