Abstract: A method and apparatus for maintaining a plurality of sequence numbers in a plurality of header compressed packets associated with an information context is described. Header compressed packets are transferred on a communication link according to a multi-layer protocol having at least a higher layer and a lower layer. If it is determined that one or more header compressed packets has been dropped, a flag is set on the header compressed packets. A sequence count at the higher layer and lower layer may be reduced by a number corresponding to the number of header compressed packets dropped. The sequence number of each of the header compressed packets is checked at the lower layer against the sequence count and renumbered to match the sequence count. If the sequence number and the sequence count match the flag is cleared. The higher layer is a PPP layer and the lower layer is a Physical Layer.

Abstract: A method and apparatus for reducing delay in the transmission of a plurality of packets by performing IP scheduling and header compression at various layers in a multilayer architecture having a plurality of classifications includes scheduling packets according to classifications. If congestion occurs during scheduling, packets may be discarded. Some packet headers may be compressed thereafter. Packets may further be queued in a first and a second queue, after scheduling, discarding, and compressing, according to at least two classifications. Best Efforts packets may be queued into the lower priority second queue. Classifications may be associated with, for example, QoS levels, delay factors, LFI, and Multilink PPP. Scheduling is performed at higher or lower layers in a multi-layer protocol. The lower layer includes a PPP layer. The lower layer may also include an HDLC layer which creates a tag for packets prior to compression being performed thereupon.