Using bundles for Web content delivery

The protocols used by the majority of Web transactions are HTTP/1.0 and HTTP/1.1. HTTP/1.0 is typically used with multiple concurrent connections between client and server during the process of Web page retrieval. This approach is inefficient because of the overhead of setting up and tearing down many TCP connections and because of the load imposed on servers and routers. HTTP/1.1 attempts to solve these problems through the use of persistent connections and pipelined requests, but there is inconsistent support for persistent connections, particularly with pipelining, from Web servers, user agents, and intermediaries. In addition, the use of persistent connections in HTTP/1.1 creates the problem of non-deterministic connection duration. Web browsers continue to open multiple concurrent TCP connections to the same server. This paper examines the idea of packaging the set of objects embedded on a Web page into a single bundle object for retrieval by clients. Based on measurements from popular Web sites and an implementation of the bundle mechanism, we show that if embedded objects on a Web page are delivered to clients as a single bundle, the response time experienced by clients is better than that provided by currently deployed mechanisms. Our results indicate that the use of bundles provides shorter overall download times and reduced average object delays as compared to HTTP/1.0 and HTTP/1.1. This approach also reduces the load on the network and servers. Implementation of the mechanism requires no changes to the HTTP protocol.