Collaborative setting of RTS/CTS in multi-rate multi-BSS IEEE 802.11 wireless LANs

Despite the fact that the Request-To-Send/Clear-To-Send (RTS/CTS) protocol significantly reduces collisions and retransmissions due to the hidden node problem, it is well known that it adds considerable overhead specially with small payload packets. The IEEE 802.11 standard defined a manageable parameter, RTS threshold, above which a data packet should be preceded with RTS/CTS handshake. In this paper, we propose new dynamic criteria for setting the RTS/CTS mechanism. We believe that RTS/CTS settings should consider the characteristics of userspsila traffic, data rates, activities and locations. While most of the algorithms proposed for controlling RTS/CTS have been investigated under single transmission rate for all users, we evaluate our criteria in a multi-rate scenario. We validate our ideas using both synthetic and real traces as well as real experiments.