摘要 |
A method for providing a roaming functionality related to an Internet Protocol Multimedia Subsystem (IMS) session includes: transmitting, by a second IMS domain, a session set-up request control signaling to a first IMS domain; transmitting, by the first IMS domain, the session set-up request control signaling in a forward direction to a Roaming Border Control Function (RBCF); and handling, by the second IMS domain, the user plane path and the associated control signaling to terminate the session set-up. Local break out of media is applied for the roaming first UE. The RBCF provides a linking of signaling received via a loop through the first IMS domain in the Home Public Land Mobile Network (HPLMN) with media anchored due to the local break out in the second IMS domain in the Visited Public Land Mobile Network (VPLMN). |