Urgent networking help in cisco router scenario

[alone1541]

Bob has a host computer with an IP address of 10.0.1.100/24 with a default gateway of 10.0.1.1 -his host network is connected via an Ethernet interface to Steve's network which has a border router of 192.168.0.1 ?

A) Bob ping the local IP address 10.0.1.200 from his host, Bob gets no reply -Steve dose some checking on his network, the only change Steve makes is to turn on a host device which has an IP address of 192.168.2.121/24 default gateway 192.168.2.1. Bob attempts to ping 10.0.1.200 again- Bob now gets a reply - explain in detail what is occurring and why Bob now gets a reply?

B) Assume Bob has no problem connecting to device on Steve's network but when Bob tries to ping any device on Steve's network he gets no reply. Explain what is going on?

 

[crimsonpc]

A) The machine that Steve powers on has a second interface with an IP address of 10.0.1.200 and actually lives on Bob's network.

B) Steve's router doesn't have a route for Bob's network. So when Bob tries to ping, the ICMP packets reach Steve's network but the response doesn't know where to go.