Skype for Business requirements for use with Pexip VMRs
This article describes the requirements and environment set-up steps for Skype for Business to use it with Pexip Service Virtual Meeting Rooms (VMRs).
Please follow the Microsoft Ports and protocol requirements documentation for each of the different environment deployments to ensure that firewalls are not blocking any communication of your Skype for Business clients or servers.
If you have an Edge Server then please refer to Edge Server environmental requirements (Port and firewall planning), and ensure that you allow outbound traffic from the Edge Server to ports 40000-49999 TCP/UDP on the Pexip Service.
- Open the Microsoft 365 Portal and go to .
Select external communication to ON.and switch
Note that you may have to wait for up to 24 hours before the setting takes effect.
You need to allow external user access on your Lync server in order to connect to a Virtual Meeting Room. We support both Dynamic and Enhanced federation. The following configuration on the Lync server is needed to be able to dial from a Microsoft Lync client to a Virtual Meeting Room.
- Go to .
- Switch on Enable federation and public IM connectivity and Enable partner domain discovery.
- Go to .
- Add a new Allowed domain and enter a Domain name of vmr.vc
No. The service will not be able to find a route back to the caller, as the Skype for Business user is local to the customer’s network only. There are no records of this user externally. Registering the same domain for Skype for Business and another service infrastructure breaks the combined protocol architecture of DNS and SIP (it violates the RFCs).
In Figure 1 below, the Skype for Business user (sfb_user) and the other video conferencing system (meeting_room) are both registered on the same domain (example.com). When the Skype for Business user calls the VMR (1), a connection is established. However, when the VMR sends a first SIP UPDATE message (2), the Pexip Service recognizes the domain is registered in own infrastructure and searches for the user. As the user is not registered, there is no route back to the endpoint and the connection terminates.
With separate domains between Skype for Business and other video users, the Skype for Business domain will not be registered on the Pexip Service, and the route back to the Skype for Business user is maintained throughout the call. To avoid additional costs for purchasing multiple domains, the calling domain for the Pexip Service can be a subdomain (e.g. vc.example.com). See Figure 2 below.