International Journal of Computer Applications (0975 – 8887) Volume 76– No.12, August 2013 32 Performance Analysis of Node Mobility in Beacon and Non-Beacon enabled IEEE 802.15.4 based Wireless Sensor Network Surender.R Department of Electronics Engineering School of Engineering and Technology Pondicherry University, Pondicherry, India P. Samundiswary Department of Electronics Engineering School of Engineering and Technology Pondicherry University Pondicherry, India ABSTRACT Recent advances in wireless communication technologies have enabled the development of Wireless Sensor Networks (WSNs) that consist of low cost, power and small-size sensor nodes. ZigBee, an IEEE 802.15.4 based wireless sensor networks have been the promise of facilitating large-scale and real-time data processing in complex environments. Mobility management is a challenging task in the IEEE 802.15.4 based wireless sensor network. Work in this paper comprises of recovery of the network in case of PAN coordinator failure using mobile node with trajectory. The simulation model consists of IEEE 802.15.4 based wireless sensor network which involves a mobile node deployed near PAN coordinator. The deployed mobile node routes through the coverage area of each PAN coordinator to recover the network. The work is also implicated with Beacon and Non- beacon enabled IEEE 802.15.4 based wireless sensor network. The simulation model is done by using OPNET. Performances metrics like throughput and delay in the network are determined and analyzed. Keywords ZigBee, IEEE 802.15.4, mobile node, trajectory, PAN coordinator 1. INTRODUCTION Rapid development of low-rate Wireless Personal Area Networks (LR-WPANs) technology has attracted a lot of attention due to its huge application space. LR-WPANs adopt IEEE 802.15.4 as a communication standard for Zigbee networks. IEEE 802.15.4 based WSN standard has also gained significant attention among researchers in recent years. The IEEE 802.15.4 standard [1] is used in the application space of industrial automation, intelligent measurement, intelligent building and remote medical care because of its low level of complexity, low cost and low power consumption. Zigbee technology aims at remote control and sensor applications, which is suitable for operation in harsh radio environments and isolated locations. IEEE 802.15.4 based WSN defines the physical and MAC layers [2]. The MAC layer of IEEE 802.15.4 standards operates in two different types of modes. They are beacon enabled and non- beacon enabled mode. Periodic transmission of beacon messages are the features of beacon enabled mode for network association and synchronization [3]. Beacon enabled can operate network-wide to maintain synchronization and allows the mode to operate on slotted Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) mechanism. On other hand, non-beacon enabled mode nodes are not synchronized, due to the absence of periodic beacon transmissions. Therefore, the decentralised communication among the nodes in this mode is facilitated by unslotted CSMA/CA mechanism [4]. Apart from the absence of periodic beacons and its consequences (e.g., absence of network-wide synchronization and superframe structure), their nature of time evolution is the major difference between slotted and unslotted CSMA/CA mechanisms. Several studies have investigated energy consumption in non-beacon enabled Zigbee WSNs [5]. A comprehensive performance evaluation of Zigbee wireless networks in beacon enabled and non-beacon enabled modes has been performed by Bilgin et al. [6]. Their results showed that the utility of either beacon enabled or non-beacon enabled mode is dependent on the specific application. However the analysis of the node mobility deployed near PAN coordinator is not examined to improve the performance in case of coordinator failure for either beacon enabled or non-beacon enabled network. An attempt has been made to implement mobile node in adjacent with the PAN coordinator for both beacon enabled and non- beacon enabled network and it is exploited in this paper. The paper is structured as follows: Section 2 presents the comprehensive view of IEEE 802.15.4 standard. Section 3 gives an overview of proposed network model in the network. Simulated results and discussion are presented in Section 4. Section 5 discusses about conclusion and future work. 2. OVERVIEW OF IEEE 802.15.4 ARCHITECTURE