Patent ID: 8000245

Claim:
A method for verifying header compression context identifiers associated with packets outputted from a network node, the method comprising: receiving, at the network node, a packet belonging to a flow, the packet including a quality of service (QoS) level required for the flow; assigning a compression context identifier to the packet as an associated context ID; storing, in a context ID table stored in a context ID storage, an entry establishing a correspondence between the flow, the required QoS value, and an associated context ID, wherein the associated context ID is a compression context identifier; generating an compressed header that includes the associated context ID; queuing the packet in a selected queue in a plurality of queues in a traffic manager based on the required QoS level of the flow; blocking the packet when a period of congestion in the traffic manager is identified; dequeuing the packet from the selected queue when the period of congestion has ended; comparing the QoS level of the packet with a QoS level corresponding to the associated context ID in the context identifier table; determining that the flow has expired when the QoS level of the packet is not the same as the QoS level corresponding to the associated context ID in the context ID table; and discarding the packet when the flow has expired.