Computer Networking Basics
In the OSI reference model, which layer uses logical addresses such as IP addresses to relay packets between different networks until they reach their destination?
- AData link layer (layer 2)
- BNetwork layer (layer 3)
- CTransport layer (layer 4)
Show answer and explanation
Answer: B. Network layer (layer 3)
The OSI reference model organizes communication functions into seven layers, from the physical layer up to the application layer. The network layer (layer 3) uses logical addresses such as IP addresses to choose a route across multiple networks and relay packets to the destination. The data link layer below it only delivers frames to a neighboring device within the same network, using MAC addresses. The transport layer handles communication between applications on the end hosts; TCP, for example, manages retransmission and ordering. In terms of equipment, routers operate at layer 3 and L2 switches at layer 2.
- A. The data link layer delivers frames to a neighboring device within the same network.
- B. Correct. The network layer handles relaying (routing) across networks.
- C. The transport layer handles communication between applications on the end hosts; it does not relay packets.