Ethernet and Token Ring are examples of this layer. Many people neither use the term PDU nor the term frame, but call every unit of data traveling over a network a "packet." See OSI model and packet.

When the destination receives the two fragments, the destination’s protocol stack must reassemble the fragments before processing the protocol data unit (PDU ... just have to look for a ...

In networking and communications, the formats, codes and procedures for transmitting a unit of data (frame, packet) from one node to another. Known as a "layer 2 protocol," the data link protocol ...

There are two main data transfer protocols -- Transmission Control Protocol (TCP) and User Datagram Protocol (UDP). If you only had to know one fact about each protocol, it's that TCP is slower ...