The Present Program option does not currently take advantage of VBSS so RDP at a low frame rate is still used.There is currently very little information available about this new functionality, and as with anything not well understood it seems to be creating more confusion than warranted.
Most of the questions have been centered around the topic of video interoperability, thanks in part to some generalized statements. With a more complete understanding of VBSS and its potential roadmap then the answers to various interoperability questions should be quite clear. While the concepts covered in this article are still applicable some of the limitations documented below are no longer valid. Make sure to also read the new article to understand the latest functionality provided by VBSS. Generically speaking it was communicated as some level of native support for H.264 content sharing coming to the Skype for Business platform. Obviously companies looking to address interoperability scenarios with SfB and their standards-based video conferencing systems would sit up and take notice to these claims. For those with a foundational understanding in the traditional video conferencing world that statement can sound odd. The H.264 standard is simply a video codec which could include anything in the actual image. The transmitted pixels could be arranged to display a smiling face captured by a camera, or instead show the familiar view of a users PowerPoint application captured by a video output device of some sort. While a standard H.323 or SIP call can support sending a second stream of video displaying this content the actual standard that makes this possible are not H264 itself. In the Microsoft world content sharing has leveraged Remote Desktop Protocol (RDP) since this ability was first provided in Office Communications Server 2005. Each of each lines of communications are separately established connections between the same endpoints, with their own streams and bandwidth utilization. While the traditional video conferencing systems use H.239 or BFCP to control the transport of the content, the actual content itself is encoded using a video codec and is sent within the same allowed bandwidth defined for the specific call. The content essentially steals bandwidth away from the main video when needed. Normally the content is encoded as an H.264 AVC video stream, but could in some cases fall back to a legacy H.263 stream. A content sharing session can be established all by itself in the LyncSfB world, but with traditional video conferencing a video call must first be placed and then content can be added to that existing call. Comparatively content sharing in LyncSfB has been of much sharper quality and resolution but severely limited in frame rate and typically more costly on the network. This optional setting still utilized RDP for the data stream but boosted the frame rate a bit (as well as the bandwidth usage). A side-by-side comparison of the default and high performance RDP options can be seen in this blog article by Skype for Business MVP Michael LaMontagne. ![]() The addition of Video Based Screen Sharing helps address some of these limitations while at the same time not negatively impacting the overall image quality that RDP has provided to date. Understand that currently this capability is only provided in the Office 2016 version of the Skype for Business 2016 client, starting with the public release of the 16.x client version (e.g. The rebranded Lync 2013Skype for Business 2015 15.x client installations do not include this capability and will continue to share content using RDP. Selecting any of the other sharing options like Present Program or Present PowerPoint Files will still behave the same as in previous clients. The PowerPoint File sharing option leverages the Office Web Apps Server which does not actually stream the content and thus VBSS is not applicable here.
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