Presence is always positioned as the key to unified communications (UC) - at the very heart of UC is the ability to discern the current status of people and resources. Which protocol will be the one used to power Presence? SIMPLE or XMPP? XMPP XMPP stands for “Extensible Messaging and Presence Protocol”. It is a streaming based protocol that routes XML messages between entities. It is mainly used for presence and instant messaging although other uses for it exist
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By Tsahi Levent-Levi | July 17th, 2008 | Filed under Standardization
Two weeks ago, RADVISION hosted the IMTC SuperOp! 2008 event. The most obvious conclusion from this event is that multimedia conferencing (or should I say Unified Communications) is getting better – at least in terms of interoperability. Without exceptions, all companies successfully connected video sessions with one another. The IMTC SuperOp! event is the main interoperability event of the IMTC. In this event multiple activity groups, each dealing with a different multimedia communications technology, gather in a single room to
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By Tsahi Levent-Levi | May 29th, 2008 | Filed under Interoperability
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 IP based services such as VoIP (with or without IMS) run over open IP networks. As such, they are susceptible to security threats similar to those in the Internet. As VoIP communications becomes widely used, the security level on it becomes essential. In this guest post, Rasa Siegberg a Senior Systems Engineer from SafeNet provides his insights to VoIP and security.] The Great IP Migration The venerable voice communications industry is undergoing one of the most significant evolutionary steps
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By Tsahi Levent-Levi | May 8th, 2008 | Filed under Technology
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
[I’ve had a chat the other day with a colleague of mine, Danny Loeb, who is the Product Manager for our SIP Server Platform. As part of his work, he needs to deal with the multi-core trend and how that changes the architecture of his product.] Multi-core is all the rage these days. Or at least this is what Intel tell us - almost every month Intel arranges a seminar, workshop, training or some other session about multi-core here in
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By Tsahi Levent-Levi | April 21st, 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
Developing a videophone or any other telecommunication client? You should start thinking seriously about IMS. Today, there are two main standards used for multimedia communications over IP: SIP and H.323, where SIP is the standard which is being adopted by most vendors today - especially in the consumer market. As 3GPP, 3GPP2, TISPAN, Packet Cable and WiMAX have all selected IMS for their next generation networks, it goes without saying that a lot of vendors will start working on IMS
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By Tsahi Levent-Levi | March 6th, 2008 | Filed under Clients
