Summary:
- The network layer is responsible for routing a packet within the subnet i.e from source to destination across various nodes in the same network or across the internet.
- This layer ensures that successful delivery of the packet to destination and to perform this, network layer has to choose routes.
- This layer is also responsible for tackling the congestion problem i.e when there are too many packets & stores at a node and forwarded to the next node.
- This layer also has to carry accounting function. The header of network layer contains the necessary information needed to facilitate the billing.
- It also contains the logical address and destination address.
To summarize the functions:
1. Routing: It chooses route for the network data.
2. Congestion control: It takes care of the congestion i.e no. of packets stored at a node to be forwarded.
3. Source and destination addresses.