However, in a Skype for Business Multipoint call, both the SIP signalling and media streams are routed via the AVMCU in the Front End Server Pool as depicted in the above diagrams. Typically, with Peer-to-Peer calls between Skype for Business clients, the media traffic bypasses the SfB Servers and goes directly between the two clients whilst the SIP signalling still goes via the SfB Servers. Media is a separate stream that may or may not follow the same path as the SIP signalling traffic. SIP Signalling is primarily the control traffic, via the SfB Servers, that facilitates the call between the endpoints. Much more information about TLS, MTLS, ICE and STUN can be found in other papers in this series. You can also see that within the Skype for Business environment, the Edge Server uses ICE (Interactive Connectivity Establishment) and STUN (Simple Traversal Utilities for NAT) to deal with NAT and traverse any Firewalls and that the Reverse Proxy uses HTTPS (HTTP over TLS) to provide secure access to Skype for Business services. As the diagrams show, all SIP communications (signalling) between Skype for Business Servers use MTLS whilst SIP communications (signalling) between Skype for Business Servers and clients uses TLS. The Skype for Business environment uses TLS (Transport Layer Security) and MTLS (Mutual Transport Layer Security) to encrypt communications and provide endpoint authentication over the Internet. Furthermore, the Skype for Business environment creates a network of trusted servers and ensures that all communications within this network are encrypted. To successfully establish a video call between two Skype for Business clients, a sequence of events must take place between the various Skype for Business servers and client devices over a variety connections that use a variety of protocols.įrom the above diagrams, we can see that Skype for Business is based on Microsofts implementation of SIP and that the Skype for Business A/V communications are basically comprised of two separate streams namely SIP Signalling and Media streams. 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.
#WHAT IS THE AUTHENICATOR APP FOR SKYPE FREE#
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.
#WHAT IS THE AUTHENICATOR APP FOR SKYPE SERIES#
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.
0 kommentar(er)
