Hybrid WLAN for data dissemination applications

Abstract

In a traditional infrastructure-based IEEE 802.11 wireless LAN, all the mobile nodes associated with an access point (AP) share the same wireless channel. In such a wireless network environment, there are two major inefficiencies: (a) load imbalance among different APs when the distribution of the location of mobile nodes is non-uniform; this might result in a situation where a lot of mobile nodes access a single AP and the rest of the APs are idle; (b) poor resource utilization; most of the mobile nodes contend for the wireless channels of APs while there are some unused and available wireless channels, which can be used to set up ad hoc groups. We propose a hybrid WLAN (H-WLAN) framework to address these two problems. First, the H-WLAN framework provides an adaptive service selection module for the mobile node to figure out a better wireless channel and the server to get its service. Second, a popularity-aware channel management module is able to integrate the ad hoc mode efficiently with the infrastructure mode by allowing mobile nodes to set up a new ad hoc group and then share their resources with other nodes within that group. The simulation results show that our H-WLAN framework can substantially (a) achieve high utilization and load balance among wireless channels with lower control overhead, and (b) provide better quality of service for the mobile nodes.