Home communication network determination

A method in a control node in a home communication network for handling an indication of the home communication network identity of a user equipment associated with a session invitation initiated by the user equipment roaming in a visited communication network, wherein the user equipment sends the session invitation to a further user equipment, the further user equipment being located in the visited communication network or a further communication network, the home communication network and the visited communication network being connected by a transit network, the method comprising:

• receiving the session invitation initiated by the visited communication network;
• determining whether the received session invitation comprises a capability indicator for transit and roaming handling in the visited communication network;
• in response to determining that the received session invitation comprises said capability indicator, modifying the received session invitation, wherein modifying the received session invitation comprises adding to the received session invitation an indication of the home communication network identity and an indication for session invitation loopback routing, thereby producing a modified session invitation comprising the indication of the home communication network identity and the indication for session invitation loopback routing;
• and
• sending the modified session invitation towards the visited communication network.

A method in a control node in a visited communication network for determining a home communication network of a user equipment roaming in the visited communication network, wherein the user equipment sends a session invitation to a further user equipment, the further user equipment being located in the visited communication network or a further communication network, the home communication network and the visited communication network being connected by a transit network, the method comprising:

• receiving a session invitation from the home communication network, the session invitation comprising an indication of the home communication network identity and an indication for session invitation loopback routing;
• determining if the session invitation comprises the indication for session invitation loopback routing;
• and
• in response to determining that the session invitation comprises the indication for session invitation loopback routing, determining the home communication network based on the indication of the home communication network identity.

A control node in a home communication network of a user equipment for handling an indication of the home communication network identity associated with a session invitation initiated by the user equipment roaming in a visited communication network, wherein the user equipment sends the session invitation to a further user equipment, the further user equipment being located in the visited communication network or a further communication network, the home communication network and the visited communication network being connected by a transit network, the control node being capable of:

• receiving the session invitation initiated by the visited communication network;
• adding an indication of the home communication network identity and an indication for session invitation loopback routing to the session invitation, if the session invitation comprises a capability indicator for transit and roaming handling in the visited communication network;
• and
• sending the session invitation towards the visited communication network, wherein the session invitation comprises the indication of the home communication network identity and the indication for session invitation loopback routing.

A control node in a visited communication network for determining a home communication network of a user equipment roaming in a visited communication network, wherein the user equipment sends a session invitation to a further user equipment, the further user equipment being located in the visited communication network or a further communication network, the home communication network and the visited communication network being connected by a transit network, the control node being capable of:

• receiving a session invitation from the home communication network, the session invitation comprising an indication of the home communication network identity and an indication for session invitation loopback routing;
• determining if the session invitation comprises the indication for session invitation loopback routing;
• and
• in response to determining that the session invitation comprises the indication for session invitation loopback routing, determining the home communication network based on the indication of the home communication network identity.