Determining L2 and L3 addresses

Determining L2 and L3 addresses
9.1.4 This page will explain how Layer 2 and Layer 3 addresses are used to route a packet.
For a packet to get from the source to the destination, both Layer 2 and Layer 3 addresses are used. Figure explains the process that occurs as a packet moves through a network.
The Layer 3 address is used to route the packet from the source network to the destination network. The source and destination IP addresses remain the same. The MAC address changes at each hop or router. A data link layer address is necessary because delivery within the network is determined by the address in the Layer 2 frame header.
The Interactive Media Activity will help students recognize physical and logical addresses.
The next page will describe the administrative distance of a route.

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