To assign members from more than one signaling group to one SIP trunk group, you must first set up the signaling groups. After setting up the signaling groups you must assign members from more than one signaling group to one SIP trunk group. You can have one signaling group per MAS.

For example, if you have three MASs within the Messaging system, you must configure three signaling groups, one for each MAS. A single SIP trunk group can then be created with members from the three signaling groups.