Making the Web faster is the goal of a recently-disclosed Google research project. The Chrome browser team announced the development of SPDY, a protocol designed to augment the HTTP protocol we all know from Web URLs.
The Chromium team claims to have successfully built “a prototype web server and Google Chrome client with SPDY support”, through which Web “pages loaded up to 55% faster.”
Speed is increasingly a Google focus, as we noted yesterday. They have an initiative called “Let’s make the Web faster.” One leading Googler floated the idea that the search engine might rank search results based on how quickly a site loads.
A sample from the SPDY discussion:
In a nutshell, SPDY adds a framing layer for multiplexing multiple, concurrent streams across a single TCP connection. The framing layer is optimized for HTTP-like request-response streams.
The SPDY session offers three basic improvements over HTTP:
- Multiplexed requests. There is no limit to the number of requests that can be issued concurrently over a single SPDY connection. Because requests are interleaved on a single channel, the efficiency of TCP is much higher.
- Prioritized requests. Clients can request certain resources to be delivered first. This avoids the problem of congesting the network channel with non-critical resources when a high-priority request is pending.
- Compressed headers. Clients today send a significant amount of redundant data in the form of HTTP headers. Because a single web page may require 50 or 100 subrequests, this data is significant. Compressing the headers saves a significant amount of latency and bandwidth compared to HTTP.