Abstract
Network life time is a critical aspect of application in wireless sensor networks (WSN). Furthermore energy consumption and security has arisen as a major aspect in network design. In this article, a study of the backoff exponent (BE) management in the Carrier Sense Multiple Access with Collision Avoidance (CSMA/CA) method under the Medium Access Control (MAC) is conducted. While BE parameter define the period of time that a node should wait before access to the channel. In this context, we propose a scheme that dynamically adjusts the IEEE802.15.4 parameters according to the queue length of each sensor node in order to improve the network life time. The performance metrics studied are energy consumption, average delay throughput and packet loss probability.