Protocol Data Unit (PDU)
What is Protocol Data Unit (PDU)?
A Protocol Data Unit (PDU) is a formatted unit of data that is transmitted between two devices using a communication protocol. It consists of a header and a payload, and it is used to transmit information between devices in a structured and standardized manner.
The header of a PDU typically contains information about the protocol being used, the source and destination of the PDU, and other control information. The payload is the actual data being transmitted, and it can contain a wide range of information, depending on the application and the protocol being used.
PDUs are used in many different types of communication protocols, including networking protocols, telephony protocols, and other types of communication systems. They are an important tool for ensuring that information is transmitted reliably and efficiently between devices.
In networking, PDUs are used at different layers of the OSI (Open Systems Interconnection) model, depending on the protocol being used. For example, in the Internet Protocol (IP), PDUs are called packets, and they are used at the network layer. In the Transport Control Protocol (TCP), PDUs are called segments, and they are used at the transport layer.