Assessing handoff control impact on QoS in wireless ATM networks

There are several factors that tend to favor the use of ATM cell transport for personal communication network (PCN). These factors include: flexible bandwidth allocation and service type selection for a range of applications, some of which are yet to be defined; efficient multiplexing of traffic from burst data/Triultimedia sources; end-to-end provisioning of broadband services over wireless and wireline networks; suitability of available ATM switching equipment for inter-cell switching; improved service reliability with packet switching techniques; and finally ease of interfacing with wired B-ISDN systems that will form the telecommunications backbone. Delivering hard QoS guarantees in the wireless domain is rather difficult since assumptions made in providing QoS guarantees in wired ATM networks,do not always hold in their wireless extension due to large-scale mobility requirements, limited radio channel resources and fluctuating network conditions. Renegotiation of resources allocated to the connection is often needed. At the same time though, the multimedia flow should be transported and presented seamlessly to the destination device with a smooth change of perceptual quality. These conditions impact our ability to deliver hard QoS guarantees in wireless ATM networks. In this paper, a model for CAC and Handoff Control is proposed for the mobility support and the provisioning guaranteed QoS in a WATM Network. The proposed architecture has a very good performance and gives the ability to support multi-class and multi-channel services. Also, this model supports the seamless delivery of scalable multimedia flows with controlled QoS. Its architecture may be extended in different wireless environments other than WATM, as due to its scalability, only small modifications are necessary.