Improving the Hybrid Data Dissemination Model of Web Documents

One of the major problems in the Internet today is the scalable delivery of data. With more and more people joining the Internet community, web servers and services are being forced to deal with workloads beyond their original data dissemination design capacity. One solution that has arisen to address scalability is to use multicasting, or push-based data dissemination, to send out data to many clients at once. More recently, the idea of using multicasting as part of a hybrid system with unicasting has shown positive results in increasing server scalability. In this paper we focus on solving problems associated with the hybrid dissemination model. In particular, we address the issues of document popularity and document division while arguing for the use of a third channel, called the multicast pull channel, in the hybrid system model. This channel improves performance in terms of response time while improving the robustness of the hybrid system. We show through extensive simulation using our working hybrid server the usefulness of this additional channel and its improving effects in creating a more scalable and more efficient web server.