Performance modeling for voice over MANET in IEEE 802.11b

In this paper, the performance evaluation model of a novel medium access control mechanism that can be transmitted real-time traffic in ad hoc networks is presented. Even though DCF and EDCA are de facto standards for wireless networks, they are insufficient for supporting real-time services such as voice calls in ad hoc networks. Because they are designed for best effort data traffics and delay critical real-time traffics in the infrastructure networks, respectively. Hence, we developed the TRCF-MAC to provide constant-bit-rate voice call services to pairs of autonomous mobile nodes operating in ad hoc networks[10]. The TRCF-MAC protocol allows the distributed nodes to reserve time slots in the PCF, where the reservation is executed by using RTS/CTS-like collision avoidance handshaking. By reserving time slots in succession of super-frames, the real-time traffics requiring a constant bit rate can be efficiently supported. Since the TRCF is a time-slot reservation based MAC, the TRCF-MAC stands in need of new back-off process different from that of IEEE 802.11 DCF as performance evaluation model. In this work we also address the back-off process of the TRCF-MAC by using the progression of differences.