LSTMAC: A LowLatency Hybrid MAC Protocol for LEO Satellite Supported IoT IoT device are usually built as edge networks in smaller areas, but with the development of technology, more and more areas without infrastructure need to be covered. LEO satellites, due to its full coverage of the Earth and relatively low latency, can provide network access for IoT system. In this paper, we propose a hybrid TDMA MAC protocol LSTMAC for IoT network based on LEO satellite, which can reduce network delay and improve the system scalability. Specifically, we design a geographic priority time slot allocation strategy which can ensure optimal load and delay, besides, we also design a continuous forward time slot allocation strategy, which guarantees realtime data while reducing the utilization of satellite resources. Then we design two algorithms based on both strategies, which can effectively reduce network delay and balance the satellite resources. The simulation experimental results are consistent with the theoretical results, which embodies the effectiveness of the algorithm.

A Distributed WeightBased TDMA Scheduling Algorithm for Latency Improvement in IoT The Internet of Things (IoT) and the Wireless Sensor Networks (WSNs) attract attention of the research communities due to their rapid and promising development. These paradigms have been predicted to play a leading role in our daily life in the near future. The limited resources and the restricted number of communication channels in these networks create new challenges especially in collision and access conflicts. To bring appropriate solutions for these problems, several works, in the literature, focus on centralized and distributed approaches. Traditional distributed protocols assume that the MAC and Routing layers act independently. Moreover, the dynamic topology and the central point of failure restrict the development of centralized techniques. In this paper, we present a distributed weightbased TDMAMAC scheduling algorithm (WBDTSA). The proposed solution takes advantage of routing information to improve the communication latency and the schedule length. Simulation results show better performance, in comparison to similar distributed channel assignment approaches. The latency is improved by 47% and the schedule length is reduced by 23%.