Page 1 Intro to Cisco Routers and RIP & IGRP Lecture 6 Hassan Shuja 04/18/2006

Page 2 Cisco Routers SOHO, Branch Office, Central Site –Different size sites will have different requirements – Review handout to determine proper router for each type of site –Some of the determining factors in selecting a router are cost, availability, throughput, and additional features –Service Providers (ISP) have a different line of routers available to them

Page 3 Cisco Routers SOHO, Branch Office, Central Site –Cisco has added the 800, 1800, 2800, and 3800 Integrated Service routers – –Integrated routers allow one box to be the router, security device, VPN Gateway, WAP, Switch, IP Telephony Call Manger, etc…

Page 4 RIP & IGRP Routing Information Protocol (RIP) –RIP updates are sent every 30 seconds –A router updates its routing table once it receives an update and increments the path metric to the destination network by 1 –RIP only maintains the best path to the remote network which is based on hop metric – Could case unoptimal paths –Routing updates are sent independently of the regularly scheduled updates –RIP is very easy to configure –RIP does not support VLSM RIP Metric –RIP only uses the hop count metric – Each hop has a value of 1 –The maximum number of hops allowed in a path are 15 – If a router receives an update that increases the metric for a network to be 16 then that network is considered to be unreachable

Page 5 RIP & IGRP RIP Configuration –RIP only requires two commands to be enabled –Example: Router(config)#router rip Router(config-router)#network Router(config-router)#network Router(config-router)#network

Page 6 RIP & IGRP Interior Gateway Routing Protocol (IGRP) – IGRP was developed by Cisco in the mid 80s – The goal was to provide a robust routing protocol with an autonomous system – Autonomous system is collection of networks under a common administration sharing a common routing strategy – Can also be thought of as a routing domain – IGRP uses a metric that factors delay, bandwidth, reliability, and load – Network administrators can change these values and influence route selection – Bandwidth metric is set on the specific interface – IGRP permits multipath routing – IGRP does not support VLSM

Page 7 RIP & IGRP IGRP Configuration –IGRP only requires two commands to be enabled –Example: Router(config)#router igrp 5 Router(config-router)#network Router(config-router)#network Router(config-router)#network

Page 8 RIP & IGRP Testing Ping –The ping command sends an ICMP echo request packet to the destination address –The destination responds back with an echo reply ICMP packet –The Ping command sends the first packet and waits for the response – If a response is received a “!” is displayed – If no response is received a “.” is displayed – The default timeout is 2 seconds – Cisco IOS sends 5 packets by default Extended Ping –Allows you to change the default ping packet settings –Most importantly allows you to specific which interface to use as the source when sending the ping packet –It allows you to also change the following things – Packet size, timeout, number of packets sent