For this experiment you need to do a lot of configuration. We set up the routers so that the ethernet 0 interface has the ip address 10.2.n.30 while the ethernet 1 interface has the ip address 10.2.m.5 where n is the same as the router, or network number, and m is the network number of the second network connected to that router. So, referring to the diagram on page 107, the ethernet 0 interface on router 3 would have the address 10.2.2.30 while the ethernet 1 interface would have 10.2.4.5. We used the number 30 for all ethernet 0 interfaces and the number 5 for all ethernet 1 interfaces. We were thinking of router 4 as connecting Net 2 to Net 4. The important thing is to choose a simple scheme and stick to it in order to simplify repetetive tasks.

Configuring the routing tables turned out to be quite interesting. The O'Reilly book, Managing IP Networks with Cisco Routers, by Scott M. Ballew turned out to be extremely helpful. The procedure turns out to be quite simple.

1. telnet to the router (requires password).

2. type "enable" (requires password).

3. You are now in global configuration mode.

4. At this point it is a very good idea to type "show run(ning)" just to see what is already going on.

5. Type "config(ure) t(erminal)". The prompt will change.

6. Type "ip route dest_addr dest_subnet_mask interface" for each network you wish to reach.

7. Hit Control-Z.

8. End your telnet session.

Suppose you are configuring router 1 in an open ring topology. For each network on the other side of router 2 that you wish to reach, you would type "ip route ip_address subnet_mask your_interface_to_router_2". It sounds so simple, but it will probably be quite interesting and reveal a misunderstanding or two. A diagram of your particular network is probably essential.

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For assistance or corrections, please contact him at lave@calvin.edu.