Virtual Interfaces and NAT Pool Assignment with the IMSG

When a BSG serves as gateway controller for a virtual BGF, the BGF and the controller communicate through virtual interfaces that are associated with media resources. You configure virtual interfaces on the BGF and these virtual interfaces are available to the BSG. The virtual interfaces define media services and their associated NAT pools. You control which media resources the BGF uses by including the default media realm in service point configurations. The default media realm is a number that matches the number of a defined virtual interface. The BGF uses the NAT pool associated with the virtual interface for traffic passing through the service point.