Which layer of the OSI model is associated with the management of sequence numbers?

The Transport Layer of the OSI model is responsible for managing sequence numbers. This layer is crucial for ensuring the reliable delivery of data between devices. It primarily deals with the segmentation of messages into smaller packets, the sequencing of these packets to maintain the correct order upon arrival, and retransmission of any lost packets.

Sequence numbers are assigned to each segment of data, allowing the receiving side to detect any gaps or missing segments. This helps to reassemble the segments in the correct order before presenting them to the session layer above. Protocols operating at this layer, such as TCP (Transmission Control Protocol), utilize sequence numbers to provide end-to-end communication, ensuring that data is delivered accurately and in the right sequence, even over unreliable networks.

The other layers of the OSI model do not have this responsibility. The Application Layer focuses on end-user services and application-level protocols. The Network Layer is concerned with routing packets across networks and does not manage sequencing. The Data Link Layer deals with node-to-node data transfer and error detection, but it operates at a lower level without the need for sequence numbers like those used in the Transport Layer.