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IPX Routes
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The system uses RIP (one of the most widely used IGPs) to dynamically
build routing tables.
RIP operates with active and passive network devices. Active devices,
usually routers, broadcast their RIP messages to all devices in a network;
they update their own routing tables when they receive a RIP message.
Passive devices, usually hosts, listen for RIP messages and update their
routing tables; they do not send RIP messages. On your system, you select
a RIP mode to determine how RIP operates, as described in “IPX RIP
Mode” later in this chapter.
An active router sends a RIP message every 60 seconds. This message
contains both the network number for each destination network and the
number of hops to reach it. In RIP, each router through which a packet
must travel to reach a destination counts as one network
hop .
Routing Tables A routing table collects information about all intranetwork segments. This
table allows a router to send packets toward their destinations over the
best possible routes.
The table contains an entry for every network number that the router
knows about. The router uses this information when the router is not
directly connected to a packet’s destination network. The routing
information table provides the address of another router that
can forward
the packet toward its destination.