An Adaptive Hybrid Channel Reservation Medium Access Control Protocol for Differentiated QoS

Abstract

In a densely deployed distributed wireless network, there may be various types of traffic with differentiated Quality of Service (QoS) requirements. However, when the network is heavily loaded, the collision increases significantly, making it difficult to guarantee the QoS of traffic. Designing an efficient Medium Access Control (MAC) protocol to guarantee the QoS of different types of traffic is an essential research direction. Channel reservation mechanism is a promising approach to improving QoS. However, few studies have focused on the channel reservation mechanism for differentiated traffic. It is difficult to take into account both the QoS of real-time traffic and the collision issue for ordinary traffic. To address this issue, this paper proposes the Differentiated Service Guarantee Adaptive Reservation Mechanism (DSGARM) protocol. A hybrid reservation mechanism is proposed by combining the absolute reservation mechanism and the relative reservation mechanism. The absolute reservation mechanism is adopted for real-time traffic. Meanwhile, the relative reservation mechanism is adopted for ordinary traffic. An adaptive algorithm is proposed to calculate the reservation parameters that meet the delay requirements based on the network conditions. The proposed work can be widely applied in the densely deployed distributed wireless network with differentiated QoS requirements. In addition, this paper establishes a mathematical model for the proposed mechanism and theoretically analyzes the performance. Simulations verify that the mathematical model provides a good approximation of the protocol performance and demonstrates the advantages of the proposed protocol.