Given the Phone Proxy Mode connections are analogous to Termination Customer Trunk Groups, Termination Vendor Trunk Groups to forward the SIP Registrations to the customer’s PBX. These Trunk Groups should be created in the customer’s Relationship.
The Termination Vendor Trunk Groups are assigned to associated with the Phone Proxy Mode connection by selecting the Trunk Group in the Main Registrar down-down list in the Phone Proxy Mode connection.
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To add a Termination Vendor Trunk Group