It has been rumored that the new 3G iPhone features a front facing camera. Assuming this is true, the camera will be used for video calling. An important question is what protocol will be used for the video calls? I have written a guest post at Smith on VoIP blog regarding the difference between 3G-324M and SIP regarding mobile video telephony. In that post I explained that currently mobile video telephony (on handsets) is made possible using 3G-324M. SIP, on
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By Tsahi Levent-Levi | May 26th, 2008 | Filed under Clients, Standardization
[The ITU have started working on a standard called the Advanced Multimedia System, or AMS. It is a communications protocol intended to solve some of the issues that plague today’s protocols and also enable functionality that is not easily achievable with current systems. I have asked Paul Jones, the rapporteur for the AMS expert group to provide some of his insights on this “standard under construction.”]One of the exciting things about the technology industry is that technology is constantly changing
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By Tsahi Levent-Levi | May 22nd, 2008 | Filed under Standardization
The IMTC’s SuperOp! event is just across the corner, and this time, I am proud to say that RADVISION will be hosting it (pdf). Companies coming to this event will be testing their products for interoperability. There are parts of the market though, that are ignoring interoperability. From my own experience, they pay dearly for it in due time. Interoperability can be viewed as a process where you hurtle your product against a product of a different vendor and
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By Tsahi Levent-Levi | May 1st, 2008 | Filed under Interoperability
VoIP clients on mobile handsets are just starting to happen. At the same time, Linux is becoming an interesting mobile platform. The problem is, Linux is quite fragmented: Android, LiMo, Qtopia are just a few of the many flavors of the popular freely available open source OS. This is not just a fragmentation of distributions, which is the case today for the desktop and enterprise Linux markets, but rather a fragmentation of user interface (UI) frameworks. The mobile UI
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By Tsahi Levent-Levi | April 28th, 2008 | Filed under Clients
There are times when de-facto standards hinder the adoption and use of services. This is the case with 3G-324M and video ring-back servers. What’s 3G-324M? 3G video telephony uses a protocol called 3G-324M. This protocol in turn, uses another protocol called H.245 for call control - with H.245, handsets signal what features and capabilities they have and negotiate the media channels that will be used in the call. H.245 includes procedures and message that allow for the opening and closing
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By Tsahi Levent-Levi | April 24th, 2008 | Filed under Standardization
[Steve Rust, GIPS VP of Business Development was kind enough to provide his views on call quality and what that means on the audio side for this blog and its readers.] If you live in the United States you may have seen a television advert for Verizon where a guy wanders around the country to gauge how good his cell phone service is in different places. His tagline: “Can you hear me now?” is well recognized. Vonage is
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By Tsahi Levent-Levi | April 17th, 2008 | Filed under Technology
Can SIP be used for consumer market devices or will it only exist in the enterprise domain? This seems like an easy question to answer - surely it is suitable for consumers as well. I met with a customer last month who is working on a videophone consumer product. Their company is specifically looking for a proprietary signaling protocol. The reason for this is: SIP is good only for the enterprise market I know for a fact that
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By Tsahi Levent-Levi | April 7th, 2008 | Filed under Clients, Technology
Around 5-6 years ago, we have started with our 3G-324M efforts. At that time, when we built the business case for a 3G-324M stack, we stated an opportunity window of 5 years only until this technology becomes obsolete. A lot of water have passed down the river since then, but the fat lady isn’t singing yet - and probably won’t in the near future. Some history 3G-324M is a protocol used by 3G mobile handsets for their video telephony needs.
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By Tsahi Levent-Levi | March 27th, 2008 | Filed under Technology
Testing a video telephony system has a lot of aspects. One of the most important ones is the resulting video quality of the system. Problem is, there’s no easy way of doing that. Two approaches exist today for video quality testing: Testing against a known video reference Testing the video without any reference 1. Testing against a known video reference If we receive a video stream that is known in advance, we can
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By Tsahi Levent-Levi | March 17th, 2008 | Filed under Technology
Video as a means of communication between people has been with us for over a decade, but it hadn’t made it mainstream yet. It seems like there is evidence of that changing.Technology wise, we are almost there: We now have the processing power, bandwidth and knowledge of how to build a video system enabling people to interact in real-time and provide good quality of experience. Only problem is, video telephony is not taking off as much as it should, but
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By Tsahi Levent-Levi | February 28th, 2008 | Filed under Clients
