Enabling end-to-end quality of service in a WLAN-wired network

Since most wireless local area networks (WLANs) eventually access a wired backbone network, there is a need to ensure end-to-end quality of service (QoS) in order to support multimedia traffic in WLAN-wired networks. The implementation of QoS at the media access control (MAC) layer in the WLAN, and IP layer in the wired network presents a challenge in enabling seamless and consistent service differentiation end-to-end. To address this challenge, this paper introduces a mapping module that enables the inter-working of WLAN IEEE 802.11-2007 enhanced data channel access (EDCA) MAC layer QoS mechanisms with wired IP layer QoS mechanisms at the boundary of the WLAN and wired network for the provision of uniform end-to-end QoS. The proposed scheme was evaluated using the EDCA QoS mechanism in the WLAN and weighted round robin (WRR) packet scheduling in the wired network. The evaluation results show that the WLAN-wired network with the inter-working module performed better than that without, in terms of service differentiation of the higher priority traffic while ensuring the non-starvation of lower priority traffic. The proposed scheme is simple to implement and standards compliant. Another advantage of the proposed scheme is the fact that it deals only with mapping traffic classes across the networks and leaves the choice of QoS implementation at the IP layer to the network operator or equipment vendor. The proposed scheme greatly improves the multimedia service assurance capabilities of a WLAN-wired network and would find wide application in rural telephony, disaster response, and military communications.