Mohsen Emami - Dept. of Computer Eng. and IT Payame Noor University PO Box: 19395-3697, Tehran, Iran
Vahid Etemadi - Dept. of Computer Eng. and IT Shiraz University of Technology Shiraz, Iran
Omid Bushehrian - Dept. of Computer Eng. and IT Shiraz University of Technology Shiraz, Iran

User demands for high quality communication are growing rapidly due to complexity and volume of communicated data in information networks. So, content distribution networks have emerged to handle users’ new needs. In these networks the goal is to increase the quality of services provided to end users by placing the access points near to users. To achieve this, distributed serves are positioned in different geographical locations and large Internet service providers throughout the world. As the current Internet infrastructure is not capable of guarantying quality of new services, a distributed middleware should build overlay networks on current Internet to provide service quality of content distribution networks. This middleware should be flexible, extensible and scalable. Component based architecture would help developing a middleware with such characteristics. In this study, architecture of a component based middleware is proposed which supports publisher/subscriber services.

Content Distribution Network, Overlay Network, Quality of Service, publisher/subscriber Introduction