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

Supplemental Lab or Challenge Activity:
1. What would you expect to see if you used these commands?
acid>sh cdp neighbors
acid>sh cdp traffic
acid>sh protocols
acid>sh ip route
acid#debug ip icmp
acid#debug ip rip
2. What would you expect to see on phreak? Try steps 1-6 over again on phreak.
3. Try this with class “B” private IP addresses that you choose.
4. Try this with class “A” private IP address that you choose.
5. Try this lab with one class “A” private IP address for the Ethernet network on
acid, a class “B” private IP address over the serial line, and a class “C” private IP
address on the Ethernet network on phreak.
6. Try this with class “C” public IP addresses that you choose.
7. Try this with class “B” public IP addresses that you choose.
8. Try this with class “A” public IP address that you choose.
9. Try mixing and matching private and public IP addresses.
10. Try adding a fourth router either before acid or after scorpion. Use it to simulate
an ISP with a loopback interface. Obviously you do not want to broadcast your
routing tables to the ISP so use a derivative of the “passive interface” command to
stop those broadcasts out the serial interface. Oh, know don’t be so
snotty…sooner or later you have to learn how to figure out things like this without
exact instructions.
So What Have I Learned Here?
After thoroughly drenching ourselves in all things RIP with two routers we decided to
tack on another router and bring our total to three. This actually introduces you to
routing protocol issues. For example, even though the middle router may be able to ping
everywhere in the network, the workstations or other routers may not be able to ping
through the middle router, which is evidence of a routing problem on the middle router.
This is actually a quite common scenario. The first thing I would do is clear the IP routes
out of the tables and check the routes again. So why don’t we have any labs with four or
five routers? Simple. If you can do three then four or five is easy. Since most classes
are short it is actually a waste of time to set up four or five routers. By the time you get
them set up for class it is time to go home. Well now off the soapbox and on to the next
lab!
Guest Router Name Derivation
More members of the Master’s of Deception (MoD) hackers ring in New York City in the
1980’s/early 1990’s. They were instrumental in starting the Great Hacker War against
the Legion of Doom (LoD) hackers ring (also from NYC). Eventually the LoD were
persuaded to cooperate with the police and helped to bust the MoD.
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