Distributed Service Level Flow Control and Fairness in Wireless Mesh Networks

IEEE 802.11s mesh networking standard supports Mesh Coordinated Channel Access (MCCA) to provide better quality of service (QoS) through channel reservation during the MAC layer channel access. According to the current QoS specifications, network traffic can be broadly classified into four classes-voice, video, background and best effort. However, MCCA does not directly support the standard service differentiation that is essential for service level QoS assurance. Further, assuring fairness among the flows of similar service classes is required for effective bandwidth utilization. Providing service differentiation along with the fairness is challenging in a distributed environment due to their non-linearity and non-additive properties. This paper uses the concept of (α, p)-proportional fairness to design a distributed method for providing service differentiation with minimum fairness guarantee. An admission control mechanism is designed over standard mesh protocols to manage the minimum service guarantee for existing flows in the network. The effectiveness of the proposed scheme is analyzed using experimental results from an IEEE 802.11n+s mesh networking testbed. The scalability and performance bound of the proposed scheme is further analyzed using simulation results.