Skype for Business Communications Environment: The above diagram shows the traffic and protocols during Application Sharing. Now let's look at Skype for Business 2015 and specifically at the communications traffic involved with A/V Conferencing and Application Sharing

SIP uses the SDP - Session Description Protocol to perform the capability exchange between endpoints during call setup this includes negotiating what common parameters (such as audio and video codecs, ports and bitrates) to use. It is not an Umbrella standard and you are free to use whatever Audio and Video codecs that are available and common to the conferencing endpoints. Hence it is called an 'Umbrella' standard.īy contrast, in terms of multimedia applications, SIP is essentially a signalling protocol. For example, the H.323 Standard defines that only the G.7XX Audio and H.26X Video codecs can be used.

You can clearly see that the H.323 Protocol Stack encompasses all the elements that make up the complete H.323 protocol. The above diagram shows the OSI Model Stack (7 layers) and corresponding TCP/IP Model Stack (4 layers) and how both the SIP Stack and the H.323 Stack fit into them. It is recommended that you look all the papers listed below for a background into Skype for Business and a detailed explanation about the Codecs, Protocols, Procedures and some of the available solutions. Whilst Lync 2013 has now been renamed Skype for Business 2015, it is generally backwards compatible with Lync Server 2013. The paper is specifically based on Skype for Business 2015. Within these papers the terms, Lync, Skype, Skype for Business and SfB, unless stated otherwise, all refer to Skype for Business Server 2015. This will form the basis for understanding the challenges that must be overcome when integrating with H.323 or SIP based systems. We will show the communications links and indicate the various protocols used between servers and devices by Skype for Business 2015 when A/V Conferencing and Application Sharing. Hence, it will focus on the communications used in A/V Conferencing and Application Sharing. This paper provides details of the Networks & Protocols used by Microsoft® Skype for Business 2015 - (Lync 2013) and is Part 3 of a series that specifically looks at Microsoft Skype for Business 2015 (Lync 2013) and the challenges and solutions for integrating Skype for Business 2015 with H.323 or SIP standards compliant videoconferencing systems.

What is skype used for