This article originally appeared in the Sept. 2012 issue of INTERNET TELEPHONY
In previous columns I have bemoaned the lack of interoperability of videophones. SIP was supposed to bring that. Apple's FaceTime is SIP-based, but the most widely used videophone service, Skype, isn't. Nor is Google (News - Alert) Talk, nor the version of video calling currently used by about 100 cellular service providers around the world, 3G-324M. Last year Google announced WebRTC, which seems likely to pull everybody together. The name WebRTC is used to mean three things:
2. All the code to implement the WebRTC API. The highest quality VoIP clients have for several years been based on code from a company called GIPS. Google acquired GIPS in 2010, and with Web RTC, open sourced all its code with a royalty-free license.
This code includes capabilities to send and receive media streams over the Internet. It also includes the GIPS voice engine: all the low-level audio and packet processing needed to make calls sound great. This means echo cancellation, packet loss concealment, jitter buffering and so on. It also includes a high quality voice codec, iSAC. For WebRTC's video codec Google provided VP8, created by a company called On2, which Google acquired in 2009.
3. A Google-run open source initiative (WebRTC.org) that hosts the WebRTC code.
There are several reasons that WebRTC seems destined for success:
- WebRTC is a browser-based technology, standardized in the W3C,making it interoperable across a multitude of devices, and embeddable in any web page.
- The major browsers will support it - Chrome, Firefox and Opera for certain and IE highly likely, leaving only Safari as a potentialholdout.
- The technology is best-in-class, and it does all the technical heavy-lifting for anybody who wants to implement a videophone client.
- Skype (News - Alert) appears to be on board for WebRTC, since the only modern voice codec specified in the IETF draft recommendation for WebRTC codecs is Opus, based on Skype's SILK.
The only remaining hurdles to perfect interoperability are Apple's (News - Alert) current non-endorsement, and the lack of a video codec in the specifications. The VP8 video codec is in the WebRTC code, and it has the advantages of being high performance, widely used and royalty-free, but it is not required in any WebRTC specification, and it is not hardware-accelerated on handsets.
The alternative to VP8, H.264, is royalty-burdened, but implemented in hardware in smartphones and tablets. This hardware implementation means that battery life will be better with H.264 than VP8. Google is presumably frantically engaging the chip vendors to incorporate hardware VP8 acceleration, but even if they succeed, that will take years to reach phones in the market.
Michael Stanford (News - Alert) has been an entrepreneur and strategist in VoIP for more than a decade. (Visit his blog at www.wirevolution.com.)
Edited by Stefania Viscusi