Dynamic guard margin CAC algorithm with ensured QoS and low CDP in heterogeneous wireless networks

This paper proposes a dynamic guard margin algorithm for connection admission control in heterogeneous wireless networks, where UMTS and WLAN systems co-exist in different tiers. The algorithm works based on the idea that a network controller should down-grade the similar or lower Quality of Service (QoS) classes of traffic during the QoS negotiation phase in handovers, instead of rejecting handover connection requests of higher QoS class of traffic. The efficiency of the proposed algorithm is evaluated and compared with the other proposed algorithms using computer simulations. The obtained results demonstrated that the proposed algorithm performs much better than the existing algorithms in terms of resource saving, number of accepted connections, number of rejected connections during handovers, and total resource utilization.