Cooperative Network and Energy Management for Reservation-based Wireless Real-Time Environments

Reservation-based bandwidth allocation mechanisms in wireless and mobile environments, such as supported by the IEEE 802.11e standard, promise to offer enhanced support for real-time services and applications (e.g., mobile multimedia). This work is concerned with the scheduling of real-time traffic during the reserved medium access periods such that the applications’ real-time communication needs are met. This is particularly challenging in systems where the bandwidth reservations are insufficient to meet all packets’ deadlines. Further, this work observes that the increasingly popular energy management technique DVS (Dynamic Voltage Scaling) can further exacerbate this problem by delaying job executions and thereby packet generation (bringing them closer to their deadlines). Finally, wireless bandwidth is often affected by environmental inferences, which will further affect network performance. This paper studies these effects and presents an adaptive and cooperative mechanism to coordinate DVS, real-time packet scheduling, and link-layer adaptation, thereby increasing the number of packets meeting their deadlines, while ensuring that systemwide energy consumption is reduced.