Cross-Layer Proactive Hybrid MAC to Prolong Lifetime of Wireless Sensor Networks

A fundamental design challenge in energy-constrained wireless sensor networks is to maximise the operational time. With increasing node density and multi-hop communications, disproportion on traffic intensity and congestion level among nodes leads to uneven battery consumption and thus the existence of failure-prone nodes. Common fault-tolerant schemes focus on routing strategies although the effectiveness of rerouting is limited by the congested medium where failure-prone nodes are located. We propose a localised proactive hybrid medium access control (MAC) approach (Pro-SSAS), where nodes that are expected to be failure-prone are enhanced with scheduling access from their senders to avoid being active during the energy-expensive contention periods. Cross-layer techniques are implemented to detect failure-prone nodes and to adapt the MAC operation. Realistic simulations have verified that Pro-SSAS significantly prolongs overall network lifetime compared with rerouting schemes.