  Due to the fact that quality of service requirements are not very strict for
all traffic types, more calls of higher priority can be accommodated by
reducing some bandwidth allocation for the bandwidth adaptive calls. The
bandwidth adaptation to accept a higher priority call is more than that of a
lower priority call. Therefore, the multi-level bandwidth adaptation technique
improves the overall forced call termination probability as well as provides
priority of the traffic classes in terms of call blocking probability without
reducing the bandwidth utilization. We propose a novel bandwidth adaptation
model that releases multi-level of bandwidth from the existing multimedia
traffic calls. The amount of released bandwidth is decided based on the
priority of the requesting traffic calls and the number of existing bandwidth
adaptive calls. This prioritization of traffic classes does not reduce the
bandwidth utilization. Moreover, our scheme reduces the overall forced call
termination probability significantly. The proposed scheme is modeled using the
Markov Chain. The numerical results show that the proposed scheme is able to
provide negligible handover call dropping probability as well as significantly
reduced new call blocking probability of higher priority calls without
increasing the overall forced call termination probability.
