Provided by: Creative Commons
Date Added: Aug 2014
IEEE 802.15.4 is a standard defined for wireless sensor network applications with limited power and relaxed throughput needs. The devices transmit data during two periods: Contention Access Period (CAP) by accessing the channel using CSMA/CA and Contention Free Period (CFP), which consists of Guaranteed Time Slots (GTS) allocated to individual devices by the network coordinator. The GTS is used by devices for cyclic data transmission. Current IEEE 802.15.4 standard restricts the beacon enabled approach to star networks, while they support multi-hop networking in mesh but with no synchronization.