Patent ID: 8191133
Filing Date: 2012-05-29
Classification: H04L

Abstract:
1. A method comprising: maintaining a single global anti-replay window having global lowest and highest sequence numbers for an Internet protocol security (IPSec) security association (SA), the single global anti-replay window being associated with individual differentiated services code point (DSCP) or DSCP group, the individual DSCP or DSCP group corresponding to individual per-DSCP anti-replay windows; pre-processing a received packet having a sequence number before packet processing using the single global anti-replay window; and post-processing the received packet after packet processing using the individual per-DSCP anti-replay windows, wherein post-processing comprises: identifying a DSCP from header of the received packet; retrieving start and end pointers of the individual per-DSCP group corresponding to the identified DSCP; and checking the sequence number with the individual lowest and highest sequence numbers in the individual per-DSCP window.