Information Technology Reference
In-Depth Information
The router, B3, receives a packet from 172.16.189.10 destined for 172.16.179.10. The router is run-
ning IOS Release 11.1 and RIPv2. No other configuration changes have been made. Use binary to
prove which route in Example 8-4 is the longest match. Make sure that you designate the bits that
must match between the IP address and the longest match route. If no route matches, simply state “No
match.”
Route 172.16.176.0/22 is the longest match.
10101100.00010000.10110011.00001010
10101100.00010000.10110000.00000000
The router, B3, receives a packet from 172.16.190.10 destined for 172.16.74.10. The router is running
IOS Release 11.1 and RIPv2. No other configuration changes have been made. Use binary to prove
which route in Example 8-4 is the longest match. Make sure that you designate the bits that must
match between the IP address and the longest match route. If no route matches, simply state “No
match.”
No match. Because Release 11.1 operates with classful routing behavior by default, B3 does not use
the default route. It discards the packet because it assumes that it has access to all available subnets of
the classful 172.16.0.0 network.
The router, B3, receives a packet from 172.16.190.10 destined for 172.16.192.10. The router is run-
ning Cisco IOS Software Release 12.0 and RIPv2. No other configuration changes have been made.
Use binary to prove which route in Example 8-4 is the longest match. Make sure that you designate
the bits that must match between the IP address and the longest match route. If no route matches, sim-
ply state “No match.”
Only the default route matches. Because Cisco IOS Software Release 12.0 operates with classless
routing behavior by default (
ip classless
), the router continues to check all available routes. Because
none match, the router will use the default route if available. B3 forwards the packet using the default
route.
Determine the Topology
Using only the partial topology in Figure 8-2 and the output from the
show ip route
command in
Examples 8-5 through 8-9, complete the topology using the following guidelines:
Add necessary devices. Each LAN has a switch as is shown for HQ.
■
Connect the devices with the appropriate cables.
■
Label the interfaces.
■
Label the networks.
■
