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
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.
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.
Datagrams TCP/IP layer 4 PDU's are called segments...
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.
The PDU (protocol data unit) @ transport layer (e.g. TCP or UDP) is called as 'segment' .
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
Frames
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.
manages the data transport between the processes running on each end host
Segements
PDU (protocol data units) -Yuriy-
Frame, packet, segment, and lastly data shows the correct order of PDU de-encapsulation when a device receives messages from a network.