An Element Shift Quorum based Medium Access Protocol for Internet of Things

Billions of mobile sensing devices in Internet of Things (IoT) collect data from surrounding environment in which the Medium Access protocol is employed. Quorum-based protocols are most important medium access control protocol (MAC) for wake-up based devices. However, existing quorum-based protocols cannot achieve both low latency and long lifetime at the same time. In this paper, a novel Element Shift Quorum (ESQ) based MAC is proposed in the sensor based systems. Data transmission is usually launched from the periphery of the network through multi hop routing to the data collector (DC), thus the data operation time of devices are different based on the distance from the DC. In the ESQ protocol, the Quorum time slot (QTS) of sensing devices is scheduled in the time when the devices just have data to process, then the latency and energy consumption can be reduced. In this way, sufficient QTS are allocated for nodes when data operation is needed, and nodes can stay at sleeping state when no data forwarding is required, thus enhancing the energy efficiency and lowering the network delay. Theoretical analysis and experimental results show that, the lifetime is increased by 16% using the proposed method. Meanwhile, the latency is reduced by a factor between 9.08%-29.32%.