Learning by Doing: CISCO Certified Network ... - SCN Research

Route Summarization with RIP
Objectives:
To further your understanding of the RIP routing protocol as it applies to subnetting
design with classful addresses. You will also view updates sent and received with RIP.
Tools and Materials:
(2) PC/workstations with protocol inspectors
(2) Routers
(2) Switches
(4) Straight-through cables
(1) DCE serial cable
(1) DTE serial cable
(2) rollover cables
Background:
By default, when you enable RIP on a CISCO router you are enabling RIP version 1.
There are two versions of RIP which, oddly enough, are called RIP version 1 (a.k.a. RIP)
and RIP version 2 (a.k.a. RIPv2). RIP (version 1) is categorized as a “classful” routing
protocol. When you enable RIP or RIPv2 the routers pass updates every 30 seconds by
default. RIP version 1 does not pass any subnet mask information with its updates. It
just “truncates” (cuts-off) any information at the classful boundary (where the network
portion stops and the subnet portion starts). In CISCO-speak: RIP uses “auto-summary”
by default which cannot be disabled. For example, a class “B” address of 143.46.86.128
with RIP version 1 would be truncated to 143.46.0.0 during its updates. Remember, class
B is network-network-host-host. RIP version 2 does pass the subnet information with its
updates, but you will learn more about RIPv2 in another lab. Confused? Yeah, me too.
Let’s “learn by doing” using a class “B” address in this lab.
Lab Design:
Lo 0 Lo 0
s0
e0
s1
e0
Workstation “A”
Workstation “B”
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