A Comprehensive Acknowledgement Mechanism for Data Transport in Wireless Sensor Networks

Having reliable communications during large scale emergency situations is of paramount importance in today’s world. In particular, broadcasting critical information to both survivors and rescue teams is an important component of emergency communications. Reliable transport protocols such as TCP are tuned to perform well in traditional networks where packet losses occur mostly because of congestion. An end-to-end effective data transport protocol is critical to the reliable transfer of information in space and for a battlefield environment. Consequently, a reliable and efficient acknowledgment mechanism is required to accommodate these unreliable communication conditions. In this paper we conduct a comparative investigation of existing data transport acknowledgment mechanisms for possible adoption in the unreliable environment of Wireless Sensor Networks. We also introduce the selective negative acknowledgment (SNACK), which is designed as a reliable retransmission mechanism for data transport, followed by a brief performance evaluation of the effectiveness of SNACK compared to the standard SACK mechanism.