The per server media session limit is 4000 sessions, regardless of the server MPU rating. Control channels are not factored (and do not count) in this number. However, it is important to note that servers with MPU ratings higher than 4000 can be used to increase the channel count of the more complex codecs like G.729 or OPUS.

The formula is MIN(Server MPU Rating / Session MPU, 4000).

If a server was calculated to have 5000 MPU:

G.711 capacity would still be MIN(5000/1),4000) = 4000.

OPUS Wideband capacity would be MIN(5000/4.5,4000) = 1111.

G.729AB capacity would be MIN(5000/2,4000) = 2500.