Throughput Improvements Using the Random Leader Technique for the Reliable Multicast Wireless LANs

Abstract

A new approach, random leader-based protocol (RLBP), is presented to overcome the problem of feedback collision in single channel multi-access wireless LANs for acquiring additional channels and reliability. It involves the selection of a leader in a multicast member group that acts as a representative for sending feedback to the sender using random delayed time. The leader sends nothing but acknowledgement (ACK) messages. For reliable multicasting, on erroneous reception of packets, the leader sends nothing resulting the receiver to prompt the retransmissions. For erroneous packets reception at receivers other than the leader, our protocol allows negative acknowledgements (NAK) from these receivers to collide with the acknowledgement from the leader (assuming that leader receives correct packets), thus destroying the acknowledgement that prompts the sender to retransmit the packets. Using an analytical model, it is shown that the proposed protocol obtains higher throughput than the delayed feedback-based protocol and leader-based protocol especially under lossy consideration.