PDU¶
Protocol Data Unit
In telecommunications, a protocol data unit (PDU) is information that is
transmitted as a single unit among peer entities of a computer network.
A PDU may contain user data or control information and network
addressing. In layered architectures of communication protocol stacks,
each layer implements protocols tailored to the specific type or mode of
data exchange, or network function of the layer. For example, the
Transmission Control Protocol (TCP) implements a connection-oriented
transfer mode, and the PDU of this protocol is called a segment, while
the User Datagram Protocol (UDP) uses datagrams as protocol data unit
for connection-less transfer. A layer lower in the Internet Protocol
Suite, at the Internet Layer, the PDU is called a packet, irrespective
of its payload type.\
