Soft reservation multiple access with priority assignment (SRMA/PA): a novel MAC protocol for QoS-guaranteed integrated services in mobile ad-hoc networks

A new medium access control (MAC) protocol-soft reservation multiple access with priority assignment (SRMA/PA) protocol-is introduced for supporting the integrated services of real-time and non-real-time applications in mobile ad-hoc networks. The SRMA/PA protocol allows the distributed nodes to contend for and reserve time slots with a RTS/CTS-like “collision-avoidance” handshake and “soft reservation” mechanism augmented with distributed and dynamic access priority control, which virtually achieves capability of the distributed scheduling to guarantee the QoS requirements of the integrated services. We have demonstrated via simulation studies that the multiplexing gain can be significantly improved without much compromising the system complexity. We also have shown that the proposed back-off mechanism designed for the delay-constrained services is useful for further improving the channel utilization