BiDirectional or Server-Initiated HTTP (hybi) --------------------------------------------- Charter Last Modified: 2010-07-29 Current Status: Active Working Group Chair(s): Joe Hildebrand Salvatore Loreto Applications Area Director(s): Alexey Melnikov Peter Saint-Andre Applications Area Advisor: Alexey Melnikov Secretary(ies): S Moonesamy Mailing Lists: General Discussion:hybi@ietf.org To Subscribe: https://www.ietf.org/mailman/listinfo/hybi Archive: http://www.ietf.org/mail-archive/web/hybi/current/maillist.html Description of Working Group: HTTP has most often been used as a request/response protocol, leading to clients polling for new data, or users hitting the refresh button in their browsers. Recent web applications are finding ways to communicate with web servers in realtime, pushing data from the server-side to the client as soon as it is available. However, these applications at present can only use a variety of HTTP mechanisms (e.g. long polling requests) to communicate with web servers bidirectionally. The Hypertext-Bidirectional (HyBi) working group will seek standardization of one approach to maintain bidirectional communications between the HTTP client, server and intermediate entities, which will provide more efficiency compared to the current use of hanging requests. A general approach is preferred, with abstract semantics that can apply to a large number of applications. The Web is the design space into which the solution will be deployed. Since the existing Web is much more complicated that it seems, the working group will document how it works first, with special attention to deployed infrastructure (e.g. web clients, intermediaries, firewalls, NATs, web servers) and programming environments. New features will be required of clients, servers, or intermediaries allowing a more scalable and robust end-to-end experience. Although multiple protocols exist as starting points, backward compatibility with these protocols is not a requirement. In particular, the working group has liaised with the W3C WebApps working group around the WebSockets protocol and the need to support the WebSocket API; as agreed by both parties, the HyBi working group will take on prime responsibility for the specification of the WebSockets protocol, taking into consideration all the requirements, needs and eventual concerns raised by the W3C WebApps working group. The draft-hixie-thewebsocketprotocol "The Web Socket protocol" is considered as the input document for the working group. Wide browser support is a goal for the bidirectional communication mechanism, however the solution should also be suitable for clients other than Web Browsers. The Working Group will work to standardize a generic solution that can work efficiently in as many of the deployed environments as possible and in particular in all the elements of the web infrastructure (e.g. web browser, generic HTTP client, HTTP server and HTTP-aware intermediaries like proxies, load balancers, caches, etc.) and it is not specific for just one. The Working Group should consider: * Implementer experience * Impact on existing implementations and deployments * Ability to achieve broad implementation * Ability to address broader use cases than those covered in the input document The Working Group will produce one or more documents suitable for consideration as Proposed Standard that will: * Define a characterization of the design space * Define a solution for the bidirectional web communication Goals and Milestones: Apr 2010 Submit a document as a working group item describing the Web Socket requirements (draft-hixie-thewebsocketprotocol will be used as a starting point for further work.) Apr 2010 Submit 'The Web Socket protocol' as working group item (draft-hixie-thewebsocketprotocol will be used as a starting point for further work.) Jul 2010 Start Working Group Last Call on the WebSocket requirements Jul 2010 Submit a document as a working group item describing the Design Space characterization Sep 2010 Submit the 'Web Socket requirements' to the IESG for consideration as an Informational document Nov 2010 Start Working Group Last Call on the Design Space characterization Nov 2010 Start of discussion about Web Socket extensions the group should work on Dec 2010 Submit the 'Design Space characterization' to the IESG for consideration as an Informational document Mar 2011 Start Working Group Last Call on 'The Web Socket protocol' Mar 2011 Prepare milestone update to start new work within the scope of the charter Apr 2011 Submit the 'The Web Socket protocol' to the IESG for consideration as a Proposed Standard May 2011 Close or recharter Internet-Drafts: Posted Revised I-D Title ------ ------- -------------------------------------------- May 2010 Aug 2010 HyBi WebSocket Requirements and Features May 2010 Oct 2010 The WebSocket protocol Request For Comments: None to date.