State management in DHT with last-mile wireless extension

Most peer-to-peer (P2P) overlays based on distributed hash tables (DHTs) focus on stationary Internet hosts. However, when nodes in the last-mile wireless extension are also allowed to join the overlay, we face immediately the problem of peer mobility. When a peer moves to a new location in the network, most existing overlays treated them as if they had left the network and joined as a new node. Often, the peer needs to use a new hash ID after it changes its network attachment point. All the state information regarding the old hash ID will be discarded by the overlay. This results in inefficiency in message delivery. In addition, other nodes cannot access the mobile peer and the information stored on it through the old ID. This chapter discusses a DHT-based overlay, called Bristle, which supports peer mobility and manages their states in the last-mile wireless extension. A mobile peer can disseminate its location information through Bristle, and other nodes can learn its movement or query its location through Bristle. Bristle forms a state management overlay for DHT-based P2P systems with last-mile wireless extension.