Interclass collision protection (ICP) model for IEEE 802.11e wireless LANs (WLANs)

Abstract

Distributed Coordination Function (DCF) in IEEE 802.11 and Enhanced Distributed Channel Access (EDCA) in IEEE 802.11e are contention-based access mechanism in wireless LAN. Both DCF and EDCA reduce collisions based on inter-frame space (IFS) and backoff mechanisms. However, collisions are unavoidable even with the two mechanisms. Especially, in the EDCA model, the collision can be classified into interclass and intraclass collision. To eliminate interclass collision in wireless LAN, we propose an interclass collision protection (ICP) scheme by employing collision protection period (CPP) after backoff. Analysis is performed for one dimensional EDCA model and for the proposed ICP based EDCA model.