Pexip Infinity and Skype for Business / Lync integration features

Pexip Infinity enhances the feature set of Microsoft Skype for Business and Lync* by providing users with their own personal Virtual Meeting Room that is available at all times, and can be used for ad hoc and scheduled meetings for any number of people.

In addition, Pexip Infinity can be used as a direct gateway between any two users, regardless of device or technology. As a gateway, Pexip Infinity enables users to join from any system to a SfB/Lync meeting. This allows non-Microsoft users with anything from web browsers to traditional group videoconferencing systems to join a SfB/Lync meeting just like any Skype for Business / Lync user.

Pexip's tight integration with SfB/Lync includes features such as simulcasting and multistreaming — see the full list of supported codecs, protocols, resilience and interoperability features.

* Note that where this documentation refers to "SfB/Lync", it represents both Microsoft Skype for Business and Lync unless stated otherwise.

Pexip Infinity as a Skype for Business / Lync gateway

Pexip Infinity can act as a gateway between SfB/Lync and standards-based endpoints. This enables SfB/Lync clients to:

  • invite H.323/SIP endpoints and registered Infinity Connect clients into a SfB/Lync meeting via manual dialout or drag and drop from the contacts list
  • use the Infinity Gateway to route incoming calls directly into an ad hoc or scheduled SfB/Lync meeting
  • when dialed into a Pexip VMR conference, invite other SfB/Lync or external contacts into that same Pexip VMR (this creates a new SfB/Lync meeting which is merged with the existing Pexip VMR)
  • receive and initiate person-to-person calls with standards-based devices, and then optionally add other participants (to escalate to a multipoint SfB meeting).

The Infinity Gateway is configured as a series of Call Routing Rules which specify which calls should be interworked and to where.

For information about to how configure the SfB/Lync gateway functionality, see Using Pexip Infinity as a Skype for Business / Lync gateway.

Simulcast from Pexip Infinity to Skype for Business / Lync AVMCU

Pexip Infinity can send the video streams of gateway participants at multiple resolutions to a SfB/Lync meeting hosted on the SfB/Lync AVMCU.

This means that if SfB/Lync clients request different video resolutions from the AVMCU, Pexip Infinity will support the equivalent request for that resolution from the AVMCU.

This optimizes the SfB/Lync user experience for all SfB/Lync meeting participants, and for all device sizes from a mobile client to the Microsoft Surface Hub.

When viewing the status of the backplane media streams via the Pexip Infinity Administrator interface, a separate stream is shown for every resolution currently being sent. This example shows 3 current simulcast streams:

Simulcast to SfB/Lync AVMCU is automatically enabled and requires no administrator configuration.

Multistreaming from Skype for Business / Lync AVMCU to Pexip Infinity

Pexip Infinity can receive multiple video streams from an AVMCU multi-party conference. This provides an enhanced conferencing experience for all participants connected to a SfB/Lync meeting:

  • Participants in a Pexip VMR that has been merged with a SfB/Lync meeting see a combined set of Pexip VMR and SfB/Lync meeting participants.
  • Participants connected to a SfB/Lync meeting via the Infinity Gateway see a full combined set of both SfB/Lync participants and any other Pexip gateway participants in the conference. They always see the default Pexip 1 +7 layout (large main speaker and up to 7 other participants), and at a resolution optimized for the participant's device, as shown below:

Note that:

  • There are always 6 video streams negotiated with the AVMCU, one in HD and the others at thumbnail resolution. However, no unnecessary resource capacity is used on Pexip Infinity if a stream is not active.

    When viewing the status of the backplane media streams via the Pexip Infinity Administrator interface, each of the 6 negotiated media streams is shown. In this example, only 2 of the 6 streams are currently active:

  • As the AVMCU can only send a maximum of 6 video streams, if more than 6 AVMCU participants are shown on the stage in a Pexip Infinity layout (as seen by Pexip VMR participants or a Pexip gateway participant), those additional AVMCU participants display as a broken camera.
  • If a SfB/Lync client pauses video or puts its call with the SfB/Lync meeting on hold, that participant is represented by a frozen image.
  • When an AVMCU participant is spotlighted, all other AVMCU participants switch to audio only:
    • Pexip VMR participants see audio indicators instead of video for all of the other AVMCU participants, but still see video from other VMR participants.
    • Pexip gateway participants see audio indicators instead of video for all other participants.

SfB/Lync AVMCU multistreaming is automatically enabled and requires no administrator configuration.

Supported codecs, protocols and resilience

Supported codecs for calls between Pexip Infinity and Skype for Business / Lync:

  • Video: H.264 UC and multistream H.264SVC (Lync 2013 and Skype for Business), and Microsoft RTVideo (Lync 2010, Lync 2013 and Skype for Business).
  • Audio: G.722.

Desktop/application window sharing, RDP and VbSS:

  • Desktop and single application windows can be shared from Skype for Business / Lync for Windows, and Skype for Business / Lync for Mac.
  • Pexip Infinity supports bi-directional RDP. Skype for Business / Lync users can send and receive dual streams.
  • Pexip Infinity supports Video-based Screen Sharing (VbSS). Pexip Infinity supports sending and receiving content via VbSS to and from Skype for Business meetings, and to and from Skype for Business clients that are either calling another endpoint via the Infinity Gateway, or calling into a Virtual Meeting Room. For information about enabling VbSS on your Skype for Business infrastructure see

Presenting PowerPoint files:

  • Pexip Infinity supports the Persistent Shared Object Model (PSOM), and supports PowerPoint presentation from Windows desktop Lync 2013 and Windows Skype for Business clients.
  • Participants that are connected to a Pexip VMR, or in a gateway call with a SfB/Lync client or SfB/Lync meeting, can see shared content if a SfB/Lync user presents PowerPoint files.
  • Requires Office Web Apps (OWA) Server.
  • Slide animation is not supported; Pexip participants will see a composite JPEG image. Also, annotations are not supported.
  • Note that a SfB/Lync client's connection to a VMR or gateway participant is automatically escalated into a SfB/Lync meeting if the SfB/Lync client presents PowerPoint files.

Packet loss resiliency:

  • Pexip Infinity supports send and receive video FEC (X-ULPFECUC) with Lync 2013 / Skype for Business clients and Skype for Business meetings.
  • Pexip Infinity supports audio FEC (RED) for audio content sent to and received from Lync 2013 / Skype for Business clients and Skype for Business meetings.
  • Pexip Infinity supports FEC on content received from Lync 2010 clients, as defined in [MS-RTVPF].

Connectivity resilience:

  • If the connection to a Skype for Business / Lync meeting is lost, Pexip Infinity attempts to re-establish the connection. Note that this does not apply to Pexip-hosted VMRs that have been merged into a SfB/Lync meeting.


The following are known limitations when integrating Pexip Infinity with Skype for Business / Lync:

  • Pexip Infinity does not support direct federation with consumer Skype; it does support federation with Skype for Business / Lync.
  • For an on-prem Pexip Infinity deployment, if there are any firewalls in between the SfB/Lync server and the Conferencing Nodes, or between the internal SfB/Lync clients and the Conferencing Nodes, these firewalls have to be configured to permit the relevant traffic (see Firewall ports for Skype for Business / Lync integrations).
  • There are some limitations with merging and escalating SfB/Lync meetings with PIN-protected Pexip conferences:
    • When using drag and drop to merge a PIN-protected Pexip conference into a SfB/Lync meeting, you need to include the PIN in the SfB/Lync contact address using the format <vmr_alias>**<PIN>@<domain>. Note that this will make the PIN visible to other SfB/Lync meeting participants. You can only merge a locked Pexip conference into a SfB/Lync meeting if the Pexip conference is also PIN-protected.
    • If a SfB/Lync client dials a PIN-protected VMR directly without the PIN in the URI, and then enters the PIN manually, it may not be able to present a PowerPoint file or escalate that call to a SfB/Lync meeting (e.g. by drag-and-dropping other SfB/Lync participants into the call). Presentation and escalation is always possible if the SfB/Lync client initially dials the VMR with the PIN in the URI.
  • Video is not sent, in either direction, between RTV-based clients and a VTC system connected into a SfB/Lync meeting via Pexip Infinity.
  • When a SfB/Lync mobile client is in a gateway call to another device, it cannot invite other external contacts into that call unless the SfB/Lync mobile client is already in an existing SfB/Lync meeting.
  • PowerPoint presentation from SfB on Mac clients is not supported.

For further information and troubleshooting, see Troubleshooting and limitations with Skype for Business / Lync and Pexip Infinity integrations.