A Hop-by-Hop Node Failure Control Protocol for Wireless Ad Hoc Networks: Towards MAC Layer Control

We present HbH a new control paradigm in order to overcome nodes failures in multihop wireless ad hoc networks. HbH is an enhancement of the IEEE 802.11 protocol, that enables packet and buffer control at the MAC layer. Previous works have shown that the use of acknowledgments at the transport layer in multihop wireless networks reduces considerably the goodput achieved by connections. Instead of using end-to-end or hop-by-hop acknowledgements, with HbH wireless nodes track neighbors transmission to know if packets are correctly delivered and to detect nodes failures. The innovation in our work is in pushing down such control to the MAC layer which allows taking advantage of the broadcast nature of the wireless medium. HbH attempts to provide a reasonable trade-off between reliability and performance as well as complexity. Our objective is also to study the effectiveness of providing end-to- end reliability by using hop-by-hop flow control. We compare the performance of our protocol in J-Sim simulator with the traditional IEEE 802.11. We show that we can increase the reliability of a UDP flow without adding control overhead thus increasing the goodput as well.