A couple of readers disagree with my posting Vidyo and the Death of QoS. Here are their unedited comments.
Marty Hollander: VP Marketing at Vidyo
Catchy headline, John! But let's clarify what Vidyo means when it speaks about QoS. Vidyo believes that QoS is important to ensure that applications perform as expected on a converged network. Business critical applications need to have priority over general Internet traffic. It is predicted by Cisco that video traffic will exceed 50%. We do not believe that video traffic needs to be given the highest priority, nor does it make sense. Yet traditional video conferencing has required the highest priority QoS. What Vidyo suggests, and our customers experiences have proven, is that VidyoConferencing does not require the highest priority, and even more so, Vidyo performs well in the context of other applications having higher priority.
As with many people who look at Vidyo technology, there is confusion about the use of an open standard codec--H.264 SVC--and the game-changing Vidyo ARCHITECTURE that dynamically adapts to deliver a natural video communication experience. This architecture utilizes a VidyoRouter to deliver rate and resolution matched video streams that dynamically adapt to changes in desired resolution and bandwidth conditions. The good news about the Vidyo architecture is that short term changes in bandwidth go unnoticed by VidyoDesktop and VidyoRoom users. These are issues that arise with our customers, and we just had a customer situation where the QoS decision was pivotal in choosing a solution:
A major company had Polycom HDX room systems that required high QoS to perform well and wanted to expand usage to the desktop. Their primary concern was that this videoconferencing traffic needed to run across their own network, but could not impact the primary business applications that were core to the business. After determining that PVX and Tandberg's Movi both required QoS changes, they decided to explore VidyoConferencing. While they were looking to purchase an initial solution with just 20 VidyoLines, during the trial period use grew so rapidly with no QoS changes that they ended up purchasing 70 VidyoLines! And their comment was that they noticed no impact on their business applications.
So, it is the uniqueness of the Vidyo ARCHITECTURE that is critical to provide the scalability to address the growth in video communications and it is correct that it uses H.264 SVC. The Vidyo architecture allows one to retain QoS for your business applications, but not require it for your video conferencing.
I look forward to seeing you next week at Enterprise Connect.
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Scott Colesworthy: founder and CEO, Soltrite
First, full disclosure, I am the principal of a Video Conferencing Service provider that is based on Vidyo technology.
There is no dispute that video consumes a lot of bandwidth and QOS will in concept guarantee that bandwidth, so high quality video calls always happen when the demand for service fits within the constraints of the QOS provisioned. This approach works very well in an environment where the end points are "fancy" room systems of known locations and quantities.
However, the world is changing now and all predictions are that the use of video conferencing will increase exponentially with PCs, Tablets and G4 smart phones now being potential end points in a video call. A QOS deployment model, in my opinion, will not scale nor be economical or even technically possible when the number of end points explode and many of them are connecting via whatever method they can such as a customer’s network, 3-4 G cellular network, home based internet....
Another factor to consider is the steady march of technology in delivering speeds not imagined possible just a few years ago. An example is the Google Experimental Fiber Network delivering speeds of 1 gigabit per second at affordable prices.
So my opinion would be to not invest time and expensive data switching hardware and software in an effort to slice up guaranteed portions of what is perceived to be a finite resource. Rather, invest in intelligent applications that detect and adapt to the variable bandwidth that is available at that moment in time; with an understanding that that bandwidth speeds will continue to increase as prices drop.
