Google Treasure Hunt: Network Question

Network Problem

Network Problem

The network question was by far the easiest one in GTH 2008 contest.

Sample question:

Below is a diagram of a computer network. The nodes are hosts on the network, and the lines between them are links. A packet is sent out from host N with a destination of Which nodes does the packet pass through on its way to the destination? (include start and final node in your answer)

After that, Google presented a list of nodes with their IP addresses, 3 different static routes and a default gateway. This is the entry for host N:

N => => =>

Pretty easy:

  1. A packet going to arrives at node N
  2. Does it match destination host? No… next try
  3. Does it match destination host? Yes!
  4. The packet is forwarded to the host having IP address (which is host B):
B => => =>

And so forth…


How would route table at host B look like?

devel@stewie:~$ route -n
Kernel IP routing table
Destination     Gateway         Genmask         Flags Metric Ref    Use Iface U     0      0        0 eth0 U     0      0        0 eth0   U     0      0        0 eth0         UG    100    0        0 eth0