Quiz Entry - updated: 2026.07.14
What are the four basic operations performed by the Network Layer?
Addressing end devices, encapsulation, routing, and de-encapsulation — these get a packet from the source host to the destination host across networks.
The Network Layer (Layer 3) performs four basic operations:
| Operation | Description |
|---|---|
| Addressing end devices | Devices must have unique IP addresses for identification |
| Encapsulation | Encapsulates Transport Layer segment into a packet with IP header |
| Routing | Directs packets toward the destination across networks |
| De-encapsulation | Receiving host removes IP header to pass segment to Transport Layer |
Key protocols: IPv4 and IPv6 are the principal Network Layer communication protocols.
Context: The Network Layer provides services for end devices to exchange data across networks. Network layer protocols forward transport layer PDUs (segments) between hosts.
Go deeper:
IP Routing Explained (NetworkDirection) — animated walkthrough of how Layer 3 moves a packet between networks.
Wikipedia — Network layer — the four functions (addressing, encapsulation, routing, de-encapsulation) in context.