Osi Model Questions Medium
Demultiplexing is a process in the OSI (Open Systems Interconnection) Model that involves the distribution of data packets received from the network layer to the appropriate transport layer protocol or application.
In the OSI Model, the transport layer is responsible for establishing end-to-end communication between two hosts. It receives data from the session layer and breaks it into smaller segments or packets. These packets are then passed on to the network layer, which adds the necessary network addressing information.
When these packets reach the receiving host, the process of demultiplexing takes place. Demultiplexing involves examining the header information of each packet to determine the appropriate transport layer protocol or application to which it should be delivered. This is done by inspecting the port numbers or other identifiers present in the packet header.
For example, in the TCP/IP protocol suite, the transport layer protocols TCP (Transmission Control Protocol) and UDP (User Datagram Protocol) use port numbers to identify the specific application or service running on the receiving host. Demultiplexing in this case involves examining the destination port number in the packet header and delivering the packet to the corresponding application or service.
Demultiplexing ensures that the data packets are correctly routed to the intended recipient, allowing for efficient and reliable communication between hosts in a network. It plays a crucial role in the OSI Model by facilitating the proper delivery of data to the appropriate destination at the transport layer.