Grouping and energy aware MAC protocol for large scale wireless sensor networks using probabilistic slot selection

Abstract

The recent development of Wireless Sensor Networks (WSNs) and the incorporation of Internet of Things (IoT) technologies have enabled their application in various industrial fields. The successful development of WSNs is affected by various factors. Particularly, the development of Medium Access Control (MAC) protocols WSNs-IoT is deemed vital. It should consider various aspects such as energy-saving, scalability for a wide number of nodes, and grouping awareness. Although numerous protocols consider these aspects in the limited view of handling the medium access, this thesis proposes Grouping MAC (GMAC) considers geographic node distribution in the environment. Such awareness enables GMAC to significantly reduce the number of collisions and prolong the network lifetime. GMAC is developed based on five cycles managing data transmission between sensors and cluster head as well as cluster head and sink. These two stages of communication increase the efficiency of energy consumption for transmitting packets. Furthermore, GMAC contains slot decomposition and assignment based on node priority and, therefore, is a groupingaware protocol. Furthermore, GMAC is extended with an energy-aware back-off model designated as GMAC Energy-Aware (GMAC-EA). Furthermore, exploiting the historical experience of successful transmissions of CSMA parts by employing Probabilistic Slot Selection (PSS) is proposed. In the developed PSS, GMAC is more capable of achieving successful transmissions because of exploiting the already gained experience to make a decentralized agreement on the distributions of slots among nodes. For evaluation, MATLAB tool was used, and eight scenarios with changing the number of sensor nodes and their locations have been performed. The scenarios have included the number of nodes changing from 150 until 400 and the number of clusters between 3 and 5. Compared with standard benchmarks IEEE 802.15.4 and industrial automation standard (ISA) 100.11a and User-Defined Grouping (UDG), GMAC protocols generate a Packet Delivery Ratio (PDR) higher than 90%. In contrast, the PDR of the benchmark is as low as 75% in some scenarios and 30% in others. Furthermore, the GMAC accomplishes lower end-to-end (E2E) delay than the least E2E delay of IEEE with a difference of 3 s. The consumed energy is 28.1 W/h for GMAC-IEEE-EA and GMACIEEE, which is less than that for IEEE 802.15.4 (578 W/h) in certain scenarios. Besides, the evaluation of two main variants of the developed GMAC with PSS, namely; IEEE 802.15.4 based and ISA 100.11a has shown a longer lifetime of GMAC IEEE PSS with competitive performance for other metrics. GMAC, GMAC-EA, and GMAC PSS are useful to enable an effective choice for large-scale WSNs MAC management.