BiDirectional or Server-Initiated HTTP (hybi)

Last modified: 2016-01-04


Applications and Real-Time Area Director


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Description of Working Group:

The BiDirectional or Server-Initiated HTTP (HyBi) working group defines the WebSocket Protocol, a technology for bidirectional communication between an HTTP client and an HTTP server that provides greater efficiency than previous approaches (e.g., use of hanging requests or long polling).

Having completed work on the core protocol (RFC 6455), the group continues to define extensions for use by WebSocket implementations. The following extensions and optimizations are currently in scope:

  1. A per-frame compression extension to improve bandwidth usage (draft-tyoshino-hybi-websocket-perframe-deflate is a likely starting point).
  2. A multiplexing extension to improve the scalability of the WebSocket protocol (draft-tamplin-hybi-google-mux is a likely starting point).
  3. Timeout-handling capabilities to reduce the chattiness of the protocol (draft-thomson-hybi-http-timeout is a likely starting point).

The working group will also serve as a discussion venue for subprotocols. However, no subprotocol is currently chartered as a deliverable, and the WG must be rechartered to work on any subprotocols.

The group will not work on an updated version of the WebSocket protocol, unless it is specifically rechartered to do so.

The group will continue coordinating with the W3C WepApps working group with respect to the above deliverables and to ensure the best match possible between the WebSocket protocol and the WebSocket API. The group will also continue coordinating with other working groups within the IETF (e.g., HTTPBIS) as appropriate.

Goals and Milestones

Done Send compression extension to IESG for consideration as a Proposed Standard
Done Issue WG last call on the per-frame compression extension
Done Adopt a WG item for the per-frame compression extension

Request for Comments


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