After the MLPPP bundle is created in the 7750 SR, traffic can be transmitted by using MLPPP encapsulation. However, MLPPP encapsulation is not mandatory over an MLPPP bundle.
MLPPP header is primarily required for sequencing the fragments. If a packet is not fragmented, it can be transmitted over the MLPPP bundle using either plain PPP encapsulation or MLPPP encapsulation. MLPPP encapsulation for fragmented traffic is shown in Figure: MLPPP encapsulation.
Figure: MLPPP encapsulation
