Hop-by-Hop TCP for Sensor Networks

Communication links in a sensor network are unstable such that running conventional TCP protocol over a high loss rate sensor networks will suffer from severe performance degradation. To handle a packet loss, conventional TCP retransmits the lost packet from its source. However, when error rate is high, it may have difficulty to deliver a packet to its destination. Considering that most applications on a sensor network prefer faster and reliable packet delivery to higher bandwidth, this paper proposes to use the Hop-by-Hop TCP protocol for sensor networks aiming to accelerate reliable packet delivery. Hop-by-Hop TCP makes every intermediate node in the transmission path execute a light-weight local TCP to guarantee the transmission of each packet on each link. It takes less time in average to deliver a packet in a high error rate and long path environment. The performance of our approach is evaluated by simulation using NS-2 simulator. Our experiments show that Hop-by-Hop TCP outperforms TCP NewReno in both throughput and average packet delivery time. The fairness requirement is also achieved while Hop-by-Hop TCP coexists with other major TCP variants