Question

What is the protocol data unit called for layer 2 in the osi model?

Answer 1

The layer 1 (Physical layer) PDU is the bit or, more generally, symbol (can also be seen as "stream"). Thelayer 2 (Data link layer) PDU is the frame. The layer 3 (Network layer) PDU is the packet. The layer 4 (Transport layer) PDU is the segment for TCP or the datagram for UDP.