Performance comparison of CAC schemes using limited access probability in two-type traffic environments

This paper presents a new call admission control (CAC) scheme that can be used for traffic prioritisation in multiservice systems. The aim is to maximise the link utilisation while maintaining the quality of service (QoS) at a desired level. To achieve a prior setting for call blocking probability ratios, a more precise and flexible approach than conventional CAC schemes are proposed by using the concept of limited access probability. Three schemes of the proposed CAC are investigated, namely (i) Fixed Limited Access Probability (FLAP), (ii) State Dependent Limited Access Probability (SDLAP) and (iii) Occupancy Dependent Limited Access Probability (ODLAP). The performance of proposed CAC is analytically derived and also compared with discrete event simulation. The results in this paper considering two traffic-type scenarios indicate that the proposed schemes are able to achieve high system utilisation while satisfying any desired level of blocking probability ratio.