Date Added: Oct 2010
Over the last decade cooperative communication in Wireless Sensor Networks (WSNs) received much attention. A lot of works have been done to propose a MAC layer that supports cooperative relaying. The majority of these works tried to adapt the IEEE 802.11 MAC protocol to sensor networks. The adapted protocols use a lot of overhead (such as the use of RTS/CTS as well as other messages used to allow cooperation) that consumes energy. In this paper the authors propose a CSMA/CA based MAC protocol that supports cooperative communication with a minimum overhead: COSMIC (A Cooperative MAC Protocol for WSN with Minimal Control Messages). Relay selection in this new protocol is performed using both the Channel State Information (CSI) and the remaining energy.