SPDY
Encyclopedia
SPDY is a networking protocol for transporting web content developed by Google
and used in accessing Google web services from their browser Google Chrome
. Google promotes the protocol in the open-source project Chromium
to augment the Hypertext Transfer Protocol
(HTTP) protocol, achieving higher transmission speed through compression, which is one of the project's key goals. The name is not an acronym, but is a shortened version of the word SPeeDY, which is essentially the form that is used in its putative logo
. However, SPDY™ is a trademark
of Google.
the transfer of several files so that only one connection per client is required.
All transmissions are TLS
encrypted and gzip
compressed by design (in contrast to HTTP, where the headers are not compressed). Moreover, servers may hint or even push content instead of awaiting individual requests for each resource of a web page.
and Chromium
utilize SPDY when communicating with Google services, such as Google Search
, Gmail
, Chrome sync and when serving Google's ads. Google acknowledges that the use of SPDY is enabled in the communication between Chrome and Google's SSL-enabled servers. SPDY sessions can be inspected in Chrome at the special URL:
Amazon's Silk
browser for the Kindle Fire
uses the protocol to communicate with their EC2 service for optimized, cloud-based web page rendering.
Mozilla Firefox
currently supports SPDY through an out-of-tree patch, the target version for mainline inclusion is Firefox 11.
There is a command line switch for Google Chrome (
Google
Google Inc. is an American multinational public corporation invested in Internet search, cloud computing, and advertising technologies. Google hosts and develops a number of Internet-based services and products, and generates profit primarily from advertising through its AdWords program...
and used in accessing Google web services from their browser Google Chrome
Google Chrome
Google Chrome is a web browser developed by Google that uses the WebKit layout engine. It was first released as a beta version for Microsoft Windows on September 2, 2008, and the public stable release was on December 11, 2008. The name is derived from the graphical user interface frame, or...
. Google promotes the protocol in the open-source project Chromium
Chromium (web browser)
Chromium is the open source web browser project from which Google Chrome draws its source code. The project's hourly Chromium snapshots appear essentially similar to the latest builds of Google Chrome aside from the omission of certain Google additions, most noticeable among them: Google's...
to augment the Hypertext Transfer Protocol
Hypertext Transfer Protocol
The Hypertext Transfer Protocol is a networking protocol for distributed, collaborative, hypermedia information systems. HTTP is the foundation of data communication for the World Wide Web....
(HTTP) protocol, achieving higher transmission speed through compression, which is one of the project's key goals. The name is not an acronym, but is a shortened version of the word SPeeDY, which is essentially the form that is used in its putative logo
Logo
A logo is a graphic mark or emblem commonly used by commercial enterprises, organizations and even individuals to aid and promote instant public recognition...
. However, SPDY™ is a trademark
Trademark
A trademark, trade mark, or trade-mark is a distinctive sign or indicator used by an individual, business organization, or other legal entity to identify that the products or services to consumers with which the trademark appears originate from a unique source, and to distinguish its products or...
of Google.
Design
The goal of SPDY is to reduce web page load time. This is achieved by prioritizing and multiplexingMultiplexing
The multiplexed signal is transmitted over a communication channel, which may be a physical transmission medium. The multiplexing divides the capacity of the low-level communication channel into several higher-level logical channels, one for each message signal or data stream to be transferred...
the transfer of several files so that only one connection per client is required.
All transmissions are TLS
Transport Layer Security
Transport Layer Security and its predecessor, Secure Sockets Layer , are cryptographic protocols that provide communication security over the Internet...
encrypted and gzip
Gzip
Gzip is any of several software applications used for file compression and decompression. The term usually refers to the GNU Project's implementation, "gzip" standing for GNU zip. It is based on the DEFLATE algorithm, which is a combination of Lempel-Ziv and Huffman coding...
compressed by design (in contrast to HTTP, where the headers are not compressed). Moreover, servers may hint or even push content instead of awaiting individual requests for each resource of a web page.
Usage
The browsers Google ChromeGoogle Chrome
Google Chrome is a web browser developed by Google that uses the WebKit layout engine. It was first released as a beta version for Microsoft Windows on September 2, 2008, and the public stable release was on December 11, 2008. The name is derived from the graphical user interface frame, or...
and Chromium
Chromium (web browser)
Chromium is the open source web browser project from which Google Chrome draws its source code. The project's hourly Chromium snapshots appear essentially similar to the latest builds of Google Chrome aside from the omission of certain Google additions, most noticeable among them: Google's...
utilize SPDY when communicating with Google services, such as Google Search
Google search
Google or Google Web Search is a web search engine owned by Google Inc. Google Search is the most-used search engine on the World Wide Web, receiving several hundred million queries each day through its various services....
, Gmail
Gmail
Gmail is a free, advertising-supported email service provided by Google. Users may access Gmail as secure webmail, as well via POP3 or IMAP protocols. Gmail was launched as an invitation-only beta release on April 1, 2004 and it became available to the general public on February 7, 2007, though...
, Chrome sync and when serving Google's ads. Google acknowledges that the use of SPDY is enabled in the communication between Chrome and Google's SSL-enabled servers. SPDY sessions can be inspected in Chrome at the special URL:
chrome://net-internals/#events&q=type:SPDY_SESSION%20is:activeAmazon's Silk
Amazon Silk
Amazon Silk is a web browser developed by Amazon for Kindle Fire. It uses a split architecture whereby some of the processing is performed on Amazon's servers to improve webpage loading performance. The frontend is based on the WebKit browser engine....
browser for the Kindle Fire
Kindle Fire
The Kindle Fire is a tablet computer version of Amazon.com's Kindle e-book reader. Announced on 28 September 2011, the Kindle Fire has a color 7" multi-touch display with IPS technology and runs a forked version of Google's Android operating system. It includes access to the Amazon Appstore,...
uses the protocol to communicate with their EC2 service for optimized, cloud-based web page rendering.
Mozilla Firefox
Mozilla Firefox
Mozilla Firefox is a free and open source web browser descended from the Mozilla Application Suite and managed by Mozilla Corporation. , Firefox is the second most widely used browser, with approximately 25% of worldwide usage share of web browsers...
currently supports SPDY through an out-of-tree patch, the target version for mainline inclusion is Firefox 11.
There is a command line switch for Google Chrome (
--enable-websocket-over-spdy) that enables an early experimental implementation of WebSocket over SPDY.