Routing Table Question

Kenrick

I don't know how to do the above network question , please guide me,thanks in advance.

routing table question.jpg

OfWolfAndMan

There are a couple components to learn when understanding this question:

1. You must know your subnetting
2. You must know what the default route does
3. You must understand what localhost means

Let's examine the first option, 142.93.45.15. 142.93.45.0 with a subnet mask of 255.255.255.128 ranges from 142.93.45.1-142.93.45.126 (Without broadcast address), therefore the destination would be this interface (0).

Now that you understand that, the next two are the same. Choose the matching (or most specific prefix) and switch it out the appropriate interface. Localhost means it resides locally off of one of the routers interface.

As for the last one, 142.93.43.65, obviously there is no specific prefix in the routing table, therefore the default route (0.0.0.0 0.0.0.0) is used and the packet is forwarded to the next hop of R3