Hi, need some help to enable direct routing for Teams. I've 500 users with Office E3 license and want to enable PBX integration to Teams (using direct routing with my own sip trunk - microsoft calling plan not yet available in my country). How many phone system add on i need to buy to enable 10 sip trunk channel ?
You need a Phone System add-on license for every single user (500), assuming every user needs to be able to dial a PSTN number or EXT on your PBX.
For IP Phones such as hallway phones or lobby phones:
You need a Common Area Phone license for every single device.
For IP Phones or Meeting Room systems:
You need a Meeting Room license for every single device.
For your SBC:
You only need concurrent call licenses, meaning you only need to license what you believe the peak number of calls would be.
User & device licensing is much different than the SBC licensing. You must license every single user that may require the capability to make a call through Direct Routing. SBCs, however, are not typically licensed in a 1:1 ratio (concurrent call:user) and are more commonly allocated in a 1:3 or 1:4 ratio, depending upon Erlang calculations.