VT-IM-CSI
Visited Terminated – IP Multimedia – CAMEL Subscription Information
CAMEL Phase 3 allows the initiation of terminating CAMEL services at the VMSC (Visited Mobile Switching Centre). The VT-CSI if present is passed to the VMSC/VLR during the Update Location procedure. VT-IM-CSI allows for this functionality to be extended to the IMS.