摘要 |
The invention provides a method of handling SIP messages in an IMS core network. The method comprises receiving a first network entity, a first SI P message that includes an identification of a served user to which the first SIP message relates. The first IMS network entity is in the served user's home network. The first SIP message is forwarded as a second SIP message to a second network entity in the served user's home IMS core network. The second SI P message includes a P-Served-User, PSU, header identifying the served user. |