The PDU (protocol data unit) @ transport layer (e.g. TCP or UDP) is called as 'segment' .
Frames
The PDU at the Network layer is referred to as a packet. A PDU at the Data Link Layer is referred to as a frame.
Datagrams TCP/IP layer 4 PDU's are called segments...
Segements
A PDU (Protocol Data Unit) is defined by which layer it is in. In the physical layer and network layer, it is synonymous with the packet, in the data link layer, it is the frame. In the transport layer, it is a datagram for UDP. A datagram holds one or more PDU's, as it is the basic unit of transferring information via packet switching.
A Protocol Data Unit (PDU) is a unit of data specified in a protocol of a given layer of the OSI model. Each layer has its own PDU: at the Application layer, it's called a message; at the Transport layer, it's a segment (or datagram in UDP); at the Network layer, it's a packet; at the Data Link layer, it's a frame; and at the Physical layer, it's a bit or symbol. These PDUs help in managing and encapsulating data as it traverses through the layers of the OSI model.
manages the data transport between the processes running on each end host
C is Deencapsulation
Application layer: Data Presentation layer: Data Session layer: Data Transport layer: Segment (TCP) or Datagram (UDP) Network layer: Packet Data Link layer: Frame Physical layer: Bit
In networking, PDU means "protocol data unit", and it is the generic name of the "packets" of data used at different levels of the network. Using the numbering of the OSI layers: At layer 2, the PDUs are called "frame". Example: An Ethernet frame, a frame-relay frame. At layer 3, the PDUs are called "packets". Example: An IP packet. At layer 4, the PDUs are called "segments". Example: A TCP segment, a UDP segment.
What is a PDU? corruption of a frame during transmission data reassembled at the destination retransmitted packets due to lost communication a layer specific encapsulation
PDU (protocol data units) -Yuriy-