Peer-to-Peer Networking Platform and Its Applications for Mobile Phones
Norihiro Ishikawa (NTT DOCOMO, Japan), Hiromitsu Sumino (NTT DOCOMO, Japan), Takeshi Kato (NTT DOCOMO, Japan), Johan Hjelm (Ericsson Research, Japan), Shingo Murakami (Ericsson Research, Japan), Kazuhiro Kitagawa (Keio University, Japan) and Nobuo Saito (Komazawa University, Japan)
Copyright: © 2009
Compared with traditional Internet technologies, peer-to-peer technologies has functions to realize resource discovery, resource sharing, and load balancing in a highly distributed manner. In addition to the Internet, new networks such as home network, ad-hoc network and sensor network are emerging. An easy prediction is the emergence of a new environment in which many sensors, people, and many different kinds of devices coexist, move, and communicate with one another over such heterogeneous networks. Peer-to-peer technology is one of the most important and suitable technologies for such ubiquitous networking since it supports discovery mechanisms, simple one-to-one communication, free and extensible distribution of resources, and distributed search to handle the enormous number of resources. The authors have designed and implemented a peer-to-peer networking platform for realizing applications, which include various applications for mobile phones. This chapter presents their peer-to-peer networking architecture, protocols, and applications for mobile phones.
In the proposed architecture, bidirectional communication entities, called peer-to-peer nodes, construct a peer-to-peer network by establishing peer-to-peer connection between them. The peer-to-peer nodes communicate one another using the peer-to-peer connections. Each peer-to-peer node has a unique ID. The key elements of our architecture are defined as follows.
Peer-to-peer node: Peer-to-peer node is an independent, bidirectional communication entity. In our architecture, it can be a mobile device, a PDA, a personal computer, a server, a workstation, or any of a variety of devices. Each node has a unique ID and communicates using the ID independent from physical networks.
Peer-to-peer network: The term “peer-to-peer network” means a logical collection of peer-to-peer nodes that have a common interest and obey a common set of policies. The connection between peer-to-peer nodes is established on mutual trust. Each peer-to-peer node can enter or depart the peer-to-peer network at its convenience. Messages are sent from one peer-to-peer node to another directly or via some intermediary peer-to-peer nodes. Routing information is discovered by broadcasting an inquiry message to the network.
Peer-to-peer message: This is data object which is sent and received between peer-to-peer nodes. The peer-to-peer message is a basic unit of exchanging data and has a unique ID.
Peer-to-peer connection: This is a communication channel established between peer-to-peer nodes. The peer-to-peer messages are transmitted across the peer-to-peer connections.
The proposed Peer-to-Peer architecture is shown in Figure 1.