Data Fragmentation Scheme with Block ACK in Wireless Sensor Networks

Reduction of power consumption and network´s life expansion are crucial for a wireless sensor network (WSN). This is typically performed by introducing low duty cycle in a sensor node. A special challenge in WSNs is transmission of a large amount of data, like images and video, that is becoming more and more required in various applications. A wireless network is very much prone to communication errors. Thus, for the efficient design, the large data messages are broken down into smaller fragments and those smaller fragments are transmitted. But this approach introduces the burden of exchanging redundant control packets increasing the energy consumption and the transmission delay. In this paper, we propose a data fragmentation scheme using a block acknowledgment (BA) mechanism to minimize the number of the control packets and delayed transmission caused by fragmentation. We implemented the proposed scheme in sensor MAC (S-MAC) and compared it with the original S-MAC through ns-2 simulation. The simulation results verify that our scheme can decrease energy consumption as well as end to end delay.