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Video comes to Lync-Skype connectivity with V2

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We just announced yesterday the availability of video chat with Lync-Skype V2. Also a much improved audio quality with the use of SILK audio codec.

Some of the features include,

Video with H.264 SVC

Scalable Video Coding (SVC) is the ideal codec for accommodating mixed environments, including devices connected over the public Internet as well as mobile devices.

SVC (Scalable Video Coding) is annex G of the baseline Advance Video Coding (AVC) standard H.264 from the joint video team made of ITU and ISO/IEC standards bodies. SVC has been specifically designed to handle the transmission of video over varied network and device environments. The sending system will include different levels for the information transmitted, which handle: frames per second, image size and quality granularity.

Receiving devices can then pick and choose what they take from this transmission in such a way as to optimize the experience on the device/network of the receiver. This approach can deliver an acceptable video quality even when incurring very high packet loss (up to 50%). This is ideal for the increasingly crowded public Internet or over mobile networks.

Enterprise-Grade Security

Another area we’re particularly proud of is an upgrade to the way in which Skype interacts with Lync at the media and media signaling levels. While Skype did use some of the standards for NAT traversal and encryption, enterprise customers wanted more. We’ve listened to the Enterprise security community and are pleased to announce support for industry standard:

  • Transport Layer Security (TLS) for signaling encryption (RFC 5246)
  • Secure RTP (SRTP ) for real time media encryption (RFC 3711)
  • STUN, TURN and ICE for NAT traversal (RFCs 5389, 5766, 5245 respectively)

To expand on this a little bit, one of the challenges with setting up peer-to-peer calls when one or both of the participants are hidden behind corporate or Internet firewalls that use network address translation or NAT, is that the participants in the call can’t see the actual IP addresses of the other party and this gets reflected in the call setup invite messages.

These three technologies (STUN, TURN and ICE) for assisting with NAT traversal issues were already implemented on the Lync side (starting back in the Office Communication Server days) and now Skype supports the same mechanisms for Lync-Skype connectivity.

Enterprise security officers will be familiar with all of these industry standard protocols, and with v2, calls involving Lync and Skype will result in better compliance with their established security policies and therefore better control of the communications on their networks.

Wide-band Audio with SILK

SILK’s wideband codec has consistently outperformed alternatives, delivering higher audio quality across a wide range of network environments including the public Internet and mobile networks. Analysis shows that improved audio quality through the use of wideband and Super wideband codecs correlates to longer calls as described in this post: https://blogs.skype.com/2010/09/28/the-power-of-silk/

We will continues to explore ways to improve call quality, and SILK’s best of breed features such as forward error correction make it an attractive option for calls over non-QoS networks such as the Internet, even when the call is initiated on the corporate network.

We expect the combined impact of video, enterprise security and best-of-breed audio that make up this release to lead to significant opportunities for enterprise customers.

You can have a look at the detailed announcement here.

Comments

  • Anonymous
    February 26, 2014
    Will SILK be used for Lync to Lync audio in the future?