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Route Redistribution
protocol will perform load balancing over the available routes. It is impor-
tant that you understand the default administrative distance of each routing
protocol and the metrics used so that you can effectively troubleshoot and
maintain an internetwork.
RIP (Routing Information Protocol) uses a simple metric called the hop
count. The hop count for a network is simply the number of routers that a
packet must pass through to reach that network. The hop-count metric does
not take into account such things as the speed or reliability of a link, just the
number of hops. In this way, RIP is similar to the AppleTalk routing proto-
col of RTMP (Routing Table Maintenance Protocol). Novell's NetWare IPX
RIP uses ticks to determine the best path to a remote network. Ticks are cal-
culated as approximately
of a second and are Novell's way of using load
and delay of the line as metrics. If the IPX RIP finds multiple paths to the
same location with the same tick count, then hops are used as a tiebreaker.
The other important characteristic of RIP that we are considering is that
RIP is a classful routing protocol. This means that the subnet mask (prefix
information) is not sent with the route updates as it is with classless routing
protocols. RIP cannot effectively work with classless routing protocols like
EIGRP and OSPF because of this reason. However, RIP version 2 sends pre-
fix information with the router updates and its routes can be redistributed
with OSPF and EIGRP, for example. To configure RIP version 2, you just
add the command version 2 under the router rip process command,
as shown below:
Router#config t
Router(config)#router rip
Router(config-router)#version 2
It is important to remember to advertise your directly attached networks
as classful addresses. However, if you have a router attached to network but are using subnets and, you
would advertise, and the routing process would find and adver-
tise your subnets. However, we see many students type the network as the network number under RIP; this command works
because the router will change it to (the classful boundary) for
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