Channel-reserved medium access control for edge computing based IoT

Abstract

Edge computing brings powerful computing service to the proximity of IoT nodes to support sophisticated applications in future Internet of Things (IoT). Considering the channel is generally shared or multiplexed by multiple nodes in wireless networks, short response packets in edge computing service processes may easily congest or conflict with other simultaneous transmissions. Then, the service latency increases and may exceed the latency constraint of computing tasks, which naturally decrease the service performance of applications. Therefore, for edge computing based IoT (EdgeIoT), it is of great necessary yet has not been studied to schedule the transmission of responses. This paper studies the transmission of responses from the perspective of the MAC layer, a channel-reserved MAC (ChRMAC) protocol is proposed to reduce the collision and latency of responses in edge computing service procedures. A latency constraint aware scheme is devised in the ChRMAC to improve the effectiveness of reservations. Besides, a backoff recovery mechanism is designed to avoid the increase of latency and collision of computing tasks after reservations. Moreover, a cross-layer framework for the implementation of ChRMAC is proposed. Simulations are conducted in ns-3 to evaluate the proposed ChRMAC. Simulation results indicate that ChRMAC can reduce the average latency of response and increase the service performance of EdgeIoT.