Packet Layer Protocol


Packet Layer Protocol or PLP is the Network Layer protocol for the X.25 protocol suite. PLP manages the packet exchanges between DTE devices across VCs. PLP also can be used on ISDN using Link Access Procedures, D channel.
There are 5 modes of PLP: call setup, data transfer, idle, call clearing, and restarting.
There are 4 types of PLP packet fields: