A Protocol for Push Information Delivery and Its Application to Contents Delivery System

摘要

Push information delivery services have been emerging as a new service over the Internet. However, most of those services are pseudo-push information delivery services where clients periodically access information delivery servers. Those pseudo--push information delivery ser- vices do not resolve issues such as scalability on the increase of clients and real-time delivery of information. While it is expected that IP multicast is a core technology for push information delivery services over the Internet, IP multicast is now at the experimental stage, and has not been fully deployed over the Internet at this time. In this paper, we propose a new architecture and protocol for push information delivery services over the existing Internet that does not support IP multicast. Our architecture satisfies the requirements on push information delivery, such as scalability on the increase of clients and real-time delivery of information. Our architecture consists of information delivery servers, relay servers and clients. TO retain the scalability of our architecture, multiple relay servers form a relationship that has a tree structure. To realize our architecture, we have defined a new protocol called Delivery Channel Management Protocol (DCMP). We have implemented a prototype system based on our architecture. In addition, we have developed a contents delivery system called RealPush network, as an application of our architecture.