Good news for Microsoft Teams fans who are considering using the tool's Voice PSTN communications, the Media Bypass is now available for direct routing with Microsoft Teams.
A quick reminder about direct routing : The "Direct Routing" direct allows you to connect your own SBC and your own PSTN operator to Microsoft Teams for user phone numbers.
The Media Bypass allows you to shorten the media path so that it connects directly between the end user and the SBC, instead of sending it through the Microsoft Phone System. For Media Bypass to work, the SBC and the Teams client must be able to connect directly to each other. If the media cannot route directly, they will seamlessly switch to routing via the Microsoft Cloud (media proxy in Azure).
How does the customer behave Teams without Media Bypass ?
Without Media Bypass, when a Teams client using direct routing places or receives a PSTN call (Sunrise network, ,UPC, Swisscom, etc.), the signaling and media flow between the SBC, cloud Microsoft (Microsoft uses the datacenter closest to SBC) and the Teams client, as shown in the following diagram
This means that the media connects to the Internet, which can be a sub-optimal network route and will certainly result in additional hops.
How does the customer behave Teams with Media Bypass ?
The media streams go through the Public IP of the SBC
It is important to understand that in the media bypass scenario, the Teams client must have routable access to the public IP address of SBC, even from an internal network.
This scenario is not common on most enterprise firewalls, so some modifications may be necessary.