The Soft Bound Admission Control Algorithm for Vertical Handover in Ubiquitous Environment

In this paper, we present SBAC (Soft Bound Admission Control) algorithm considering critical bandwidth ratio to reduce handover blocking probability over WLAN and WAAN (Wide Area Access Network). SBAC algorithm utilizes dynamically optimized resource allocation scheme to decrease the blocking probability of vertical handover connections within the limited capacity of system. Based on SBAC algorithm, we derive the handover blocking probability as new traffic load and handover traffic load increase. In order to evaluate the performance, we compare SBAC algorithm against traditional nonbounded and fixed bound schemes. Numerical results show that the SBAC scheme improves handover blocking probability in ubiquitous environment.