Performance evaluation of 802.15.4 Medium Access Control during network association and synchronization for sensor networks
Faculty of Computing, Health and Science
School of Engineering / Centre for Communications Engineering Research
A key aspect of a wireless sensor network is its ability to self-organize and maintain connectivity. Medium Access Control (MAC) protocol manages network self-configuration, which includes establishing a personal area network (PAN), finding a network to associate or disassociate with, and synchronizing if required. Currently, there is limited research that addresses the network initialization phase. This paper provides a performance evaluation of the 802.15.4 MAC during device association and synchronization with the PAN coordinator. Our results show the impact of beacon interval and the number of associating nodes in terms of association time delay and energy consumption in stationary wireless sensor networks. Results illustrate that energy consumption and association time increase with increasing number of nodes associating with a coordinator. Moreover, short beacon intervals consume more energy due to the frequency of beacon frames that nodes have to keep track of to maintain synchronization. However, short beacon intervals reduce the time required for the nodes to associate, in contrast to longer beacon intervals that are undesirable for real time and mobile applications. Furthermore, for longer beacon intervals, BO= 12 to BO=14, there is an abrupt increase in energy consumption as the number of associating nodes increase, even for as few as as four nodes.