A single G450 Branch Gateway can be configured to support up to 320 media-processing channels. You can use the following algorithm to determine the required number of G450 Branch Gateways to support the specified call usage.
Procedure
Determine the total call usage for media processing as follows:
total usage =
G.711 unencrypted CUR + G.711 encrypted CUR + G.729 unencrypted CUR + G.729 encrypted CUR + G.726 CUR + unencrypted T.38 fax and modem over IP CUR
Determine the required number of media processing channels:
Apply an Erlang formula (mixed Erlang B / C is ideal, but pure Erlang B would also work) to the total usage and a suitable Grade of Service (for example, P001) to obtain the total number of media processing channels required.
Determine the required number of media processing channels.
Divide that number by 320 and round up to get the required number of G450 Branch Gateways.
