CCNA Introduction to Networks Practice Test 2026 – Complete Exam Prep

The correct answer is the Network Layer, which is the third layer of the OSI model. This layer is responsible for the routing of data packets between devices across different networks. It uniquely identifies devices on a network using network addresses, such as IP addresses, facilitating efficient data transmission from the source to the destination across interconnected networks.

Functions at this layer include logical addressing, which allows for packet forwarding based on the destination IP address, as well as determining the best path for data to travel across the network. The Network Layer works closely with routing protocols to manage these processes, ensuring that data can find its way through multiple hops and various networking devices.

In contrast, the other layers do not serve this specific function. The Physical Layer deals with the actual transmission of raw bitstreams over a physical medium, while the Data Link Layer is focused on node-to-node data transfer and framing. The Transport Layer, on the other hand, is responsible for end-to-end communication and error recovery, ensuring complete data transfer. Therefore, the identification of the network address is a key role that is distinct to the Network Layer.