Google SPDY: Protocol to Speed Up the Internet

As per the claims, it’s 64% faster. This is possible because SPDY allows many concurrent HTTP requests to run across one TCP session and to make SLL the standard transport protocol.

Google reminds everyone that SPDY is not a replacement for HTTP. It uses HTTP methods and headers, but it overrides the parts of the protocol that manage connections and data transfer formats. So it sits on HTTP and mods it for good.

Google will soon release an open-source SPDY-enabled web server and  SPDY-enabled version Chrome can be downloaded here.

SPDY white paper

According to Google, these are the basic improvement of SPDY over HTTP:

1. 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.
2. 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.
3. 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.