FQ-EDCA: An extension of EDCA to improve fairness in ad-hoc wireless network

IEEE 802.11e (EDCA) standard is concerned to support QoS in wireless ad-hoc networks. However, EDCA cannot control traffic when there is a congestion to guarantee QoS required by real-time and multimedia applications. Therefore, the ill-behaved sources consume the most of bandwidth allowed. That leads to some of source nodes (i.e. out-ranged nodes) suffer from the lack of bandwidth and unfairness. So, without a proper control mechanism, this leads to degrade the guarantee services. Our proposition (FQ-EDCA) is a fairness queuing model for EDCA. This paper aims to evaluate its scalability and its robustness. It enhances the QoS of EDCA by implementing a hierarchical scheduling techniques and improving the architecture of EDCA scheme. Thereby, the traffic is regulated between the source nodes. Thus, the bandwidth is distributed fairly between all the source nodes. As a consequence, these nodes can transmit their packets fairly with respect to the EDCA specifications. Moreover, the end-to-end delay of packets for the flows of the same priorities is bounded (i.e. for outranged source nodes). Therefore, the services guarantees of QoS is enhanced by FQ-EDCA, which is proved and analyzed by experimental simulations for large scale topologies.