%0 Journal Article %T Admission Control for Multiservices Traffic in Hierarchical Mobile IPv6 Networks by Using Fuzzy Inference System %A Jung-Shyr Wu %A Shun-Fang Yang %A Chen-Chieh Huang %J Journal of Computer Networks and Communications %D 2012 %I Hindawi Publishing Corporation %R 10.1155/2012/109685 %X CAC (Call Admission Control) plays a significant role in providing QoS (Quality of Service) in mobile wireless networks. In addition to much research that focuses on modified Mobile IP to get better efficient handover performance, CAC should be introduced to Mobile IP-based network to guarantee the QoS for users. In this paper, we propose a CAC scheme which incorporates multiple traffic types and adjusts the admission threshold dynamically using fuzzy control logic to achieve better usage of resources. The method can provide QoS in Mobile IPv6 networks with few modifications on MAP (Mobility Anchor Point) functionality and slight change in BU (Binding Update) message formats. According to the simulation results, the proposed scheme presents good performance of voice and video traffic at the expenses of poor performance on data traffic. It is evident that these CAC schemes can reduce the probability of the handoff dropping and the cell overload and limit the probability of the new call blocking. 1. Introduction Since the next generation networks will be unified networks based on IP architecture, the design of IP-based mobility management schemes becomes necessary. The IETF MIPv6 (Mobile IPv6) [1] and its extension were proposed for efficient mobility management. HMIPv6 (Hierarchical MIPv6) [2] manages the mobility of an MN (Mobile Node) using both a router located in the MN¡¯s home domain and a router located in a domain visited by the MN. Local movements of the MN are hidden from the outside of the visited domain. The HMIPv6 can reduce the amount of signaling and improve the performance of handover latency. Although much research [3, 4] focuses on modified Mobile IP to get better efficient performance, there are few research papers to discuss admission control scheme when considering handover and mobility management [5]. CAC (Call Admission Control) has to be revised to deal with the anticipated new composite radio wireless environment [6]. The ratio of the reserved bandwidth is adjusted to make CAC in the Mobile IP networks in [7]. Because the blocking probability, dropping probability and cell utilization are sensitive to the reserved bandwidth, it is challenge in deciding how to adjust this ratio. The utilization of the wire line link between HA (Home Agent) and FA (Foreign Agent) is used to make CAC in [8, 9]. Because the wireless links are much easier to be the bottle neck than the wire line link, it is not proper to use the utilization of the wire line link alone. Good CAC schemes have to balance the new call blocking and the handoff call blocking %U http://www.hindawi.com/journals/jcnc/2012/109685/