Which TCP/IP layer aligns with the Network layer of the OSI model?

The correct answer is that the TCP/IP layer that aligns with the Network layer of the OSI model is the Internet layer. This alignment is based on the fundamental roles that these layers play in facilitating communication over a network.

In the OSI model, the Network layer is responsible for packet forwarding, including routing through intermediate routers. It handles logical addressing (such as IP addresses) and is key for determining the best path for data to travel across a network. Similarly, the Internet layer in the TCP/IP model performs comparable functions, managing the delivery of packets from the source host to the destination host across multiple networks. It utilizes Internet Protocol (IP) for addressing and routing.

The Link layer in the TCP/IP model, on the other hand, is responsible for the physical transmission of data and the framing of packets for the local network, which corresponds more closely to the OSI model's Data Link layer. The Transport layer in the TCP/IP model corresponds to the OSI Transport layer, focusing on end-to-end communication and error recovery. Lastly, the Application layer in TCP/IP aligns with the functionality of the OSI Application, Presentation, and Session layers, dealing with high-level APIs and user interface issues rather than the routing and addressing that occur in the Internet