Pre-authentication and Selection of suitable target Base Station during Handover procedure in Mobile WiMAX Network

-WiMAX (Worldwide Interoperability for Microwave Access) is an emerging technology that can provide wireless broadband access at the data rates of 70 Mbps over 50 kilometres to both home and business customers. WiMAX is cost effective and offers higher data rates than other wireless networks. It supports both fixed and mobile applications. WiMAX is easier to deploy as compared to other networks and has flexible network architectures. One of the major challenges concerning the performance of Mobile WiMAX is seamless handover. IEEE 802.16e standard for Mobile WiMAX defines two kind of soft handovers (MDHO and FBSS) and hard handover. But only hard handover mandatory in the standard and Mobile Station cannot transmit or receive data packets during this hard handover. Therefore this long interruption due to hard handover is awful for real-time applications. Reauthentication of Mobile Station and selection of suitable target Base Station are two time-consuming processes within handover procedure. We proposed Pre-authentication scheme in which standard EAP authentication is skipped if Mobile Station handovers from one Base Station to another within he same network so handover latency will be reduced significantly. The modified MOB_5BR-ADV message contains useful information e.g. list of neighbouring Base Stations and number of real-time connections each of these Base Stations have etc. which can be helpful to calculate suitability index for selection of target Base Station. In the end we evaluate our proposed scheme by simulation using 5S-2. The results show that our proposed scheme is more efficient than traditional handover scheme. KeywordsMobile WiMAX, Re-authentication,