Mobile Chord: Enhancing P2P Application Performance over Vehicular Ad Hoc Network

Chord is a popular structured peer-to-peer (P2P) protocol. To provide P2P application service on vehicular wireless networks, chord overlay on vehicular ad hoc network (VANET) is applied. Most P2P protocols, including Chord, are designed for wired-line network, and might perform poorly in mobile networks. We propose Mobile Chord (MChord) enhancement to improve the performance of Chord over VANET. These techniques are aggressive table update, overlay table broadcasting, greedy forwarding, and passive bootstrapping. We also take network layer traffic into protocol design consideration to alleviate congestion. Through realistic vehicular mobility simulations on NS-2 platform, we find the proposed mobile chord outperforms the original chord in various aspects such as application layer forwarding steps, query response, correct query response, and application delay.