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Google's SPDY On Its Way To Standardization

The HTTPBIS Working Group intends to release an Internet draft of HTTP 2.0 by May of this year and provide a proposal for standardization until July 2013.

Part of that proposal may be at very least a partial integration of Google's SPDY, a technology that was designed to overcome some of the performance shortcomings of HTTP, which was first documented in 1995. Both TCP and HTTP are considered bottlenecks for data downloads today as Internet users have moved well beyond the simple text content HTTP was developed for. HTTP has been questioned because of its latency issues as the protocol can only fetch one resource at a time and servers cannot communicate with a client without a client request. HTTP also uses uncompressed and redundant request and response headers, which are sources for latency. SPDY still uses TCP as the underlying transport layer, but addresses some of the latency problems in HTTP.

SPDY creates room for unlimited connection streams, can prioritize and even block requests if a communication channel gets overloaded and supports header compression. SPDY also allows the server to communicate with a client without a client request. Google, which pioneered SPDY and has been supporting the technology on all of its sites and via its Chrome browser, explained that SPDY uses HTTP methods, headers and “other semantics.” However, the connection management and data transfer formats are modified to achieve up to 60 percent acceleration in page load times, especially on devices with slower Internet connections. Chrome users can monitor SPDY connections via the local URL type chrome://net-internals/#spdy in their browser.

Nottingham wrote that a second browser (Firefox) has integrated SPDY and his communication with "folks" suggested that "the time is ripe to start work on a new version of HTTP in the IETF". Google added a somewhat related, but separate idea to speed up TCP. Developer Yuchung Cheng posted a few thoughts how TCP could be improved, including an increase of the TCP congestion window, a reduction of the TCP timeout, the use of TCP Fast Open and the use of proportional rate reduction for TCP. Cheng said that Google will be posting details how to make TCP faster in the near future.