What is the network layer?
The network layer is layer 3 in the OSI (Open Systems Interconnection) model. It is responsible for packet forwarding, including routing through intermediate routers. The network layer handles logical addressing and determines the best path for data to travel from source to destination.
Key functions of the network layer
- Routing: Determining the optimal path for data packets
- Logical addressing: Using IP addresses to identify devices
- Packet forwarding: Moving packets from one network to another
- Fragmentation: Breaking large packets into smaller ones for transmission
Network layer protocols
The primary protocol at the network layer is the Internet Protocol (IP), including IPv4 and IPv6. Other protocols include ICMP (Internet Control Message Protocol) and IPsec (Internet Protocol Security).