Microsoft proposal for real time communication on the web

Microsoft has submitted its own proposal for a web real-time communication API to the W3C's Web Real-Time Communication (WebRTC) working group. A draft of the WebRTC standard, which uses JavaScript APIs to implement web-based audio and video communication in browsers without requiring additional plugins, has been around for a while now. However, Microsoft believes that that proposal, submitted by Google, Apple, Mozilla and Opera, does not offer sufficient flexibility or future-proofing, and isn't simple enough to implement.

The company says that a future-proof standard needs to be compatible with the key web tenet of statelessness, to be able to react to changing network quality, and to harmonise with a mature, diverse communications landscape across many different device classes. Microsoft notes that It must also be flexible: there should also be no fixed ties to specific codecs, media formats or other scenarios.

The architecture of CU-RTC-Web
Source: HTML5Labs Microsoft would like to implement these ideas through its cumbrously-monikered "Customizable, Ubiquitous Real Time Communication over the Web" (abbreviated to CU-RTC-Web) proposal. In submitting its proposal, Microsoft would appear to have one eye on the future of Skype, which it acquired last year. One of Microsoft's problems with the current WebRTC proposal is that it only considers video communication between browsers, ignoring VoIP and mobile phones.

Skype developers have been working on a web-based version of the VoIP service for some time, set to be integrated into the recently unveiled successor to Hotmail, Outlook.com. Microsoft's proposal, in which tech luminaries such as Skype architects Matthew Kaufman and Martin Thompson, Jonathan Rosenberg (the inventor of SIP) and Bernard Aboba (Microsoft's Lync architect) were involved, calls for a flexible, real-time-capable peer-to-peer transport layer.

It will dispense with the VoIP protocol stack's "unnecessary state machines" and complex Session Description Protocol (SDP). In their place it proposes a simple, transparent object base. It also promises developers user friendly interaction with the W3C's getUserMedia API, which enables web applications to address microphones and cameras from within a browser.

Whilst Chrome, Firefox and Opera are already offering experimental versions of WebRTC, Microsoft prefers to await further developments. The company says that it wants to implement a fixed, agreed standard in Internet Explorer, and that until then it may implement services such as Skype via temporary browser plugins.

See also:

• Chrome 21 arrives with new API for video and audio communication, a report from The H.
  
• Google open source WebRTC for open video/audio chat, a report from The H.

(Harald M. Genauck / crve)