Explanation/Reference:
Explanation:
What does a router do with a packet received from one network and destined for another network? The router performs the following three major steps:
Step 1. De-encapsulates the Layer 3 packet by removing the Layer 2 frame header and trailer.

Step 2. Examines the destination IP address of the IP packet to find the best path in the routing table.

Step 3. If the router finds a path to the destination, it encapsulates the Layer 3 packet into a new Layer

2 frame and forwards the frame out the exit interface.
Reference: http://www.ciscopress.com/articles/article.asp?p=2180208&seqNum=8