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Dynamic Routing Updates 2 ???

Hi, if I were to use the Dynamic Routing Protocols such as RIP,IGRP, or EIGRP and I have say two routers connected end-to-end from one office to another with a 64 kbps leased line.

If I were to add the network route on router, do I need to add the same route on the other router ? Does dynamic routing protocol help to update the routing table from one router to another router ?

If there are some telco routers involved in between these two routers, come to adding new network routes, how do I add those routes to those telco routers ?

Please help out.


Re: Dynamic Routing Updates 2 ???


Normally the telco provides just the physical connectivity (transport) between the sites. You normally don't route with the carrier unless it is a Internet connection.

You would put the leased line interface IP subnet under the routing process on both routers. This enables RIP, IGRP, EIGRP, etc on that interface so the router knows to send/receive updates on that interface for that protocol. Since both routers have the leased line interface network as a directed network in their routing table they know how to get there directly and not throuh RIP, etc. Now if the remote router wants to reach the central sites Ethernet interface IP network then you need to put that network under RIP/IGRP/EIGRP if using a dynamic routing protocol or configure static routes to that network on remote and vice versa.

Example network setup:

10.1.1.x/24 ---R1 ------leased line------R2----172.16.1.x/24

leased line IP is 192.168.1.x/24

Both R1 and R2 know about 192.168.1.x (directly connected)

R1 knows about 10.1.1.x/24 but doesn't know about 172.16.1.x

R2 knows about 172.16.1.x/24 but not 10.1.1.x

Now you turn on RIP, etc

On R1:

router rip



On R2:

router rip



Now both R1 and R2 will have a Rip learned router for other routers Ethernet network. Might take up to 30 seconds for the RIP update.

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