Which layer of the OSI model is responsible for path selection between the source and destination?

The Network layer, which is the third layer of the OSI model, is primarily responsible for path selection between the source and destination. This layer facilitates the routing of data packets across diverse networks, enabling them to traverse different routers and network topologies. In essence, the Network layer determines how data is forwarded based on logical addressing, typically using IP addresses.

Protocols such as IP (Internet Protocol) operate at this layer and play a crucial role in defining how packets are routed, managing the addressing and traffic control necessary for efficient data transmission. The ability to find the best available path for data to travel from one point to another is what makes this layer essential for inter-network communications.

In contrast, the Data Link layer focuses on creating a reliable link between adjacent network nodes on the same physical medium and does not concern itself with the overall path selection. The Transport layer is dedicated to ensuring the complete data transfer, managing error corrections, and maintaining the reliability of communication, while the Session layer is responsible for managing sessions or connections between users but does not handle path selection.