Method of operating a telecommunications network

A method of operating a cellular telecommunications network, said network forming part of a telecommunications network, in turn also comprising a non-cellular telecommunications network, wherein both the cellular telecommunications network and the non-cellular telecommunications network are accessible to a User Equipment, UE, the method comprising the steps of:

• participating in establishing a network connection between the UE and the cellular telecommunications network via the non-cellular telecommunications network;
• obtaining a:
• unique cellular subscriber identity associated with the UE and for accessing the cellular telecommunications network;
• and
• network address associated with the UE and for use with the non-cellular telecommunications network for the network connection;
• generating an identifier for identifying the UE to the non-cellular telecommunications network;
• generating a mapping between the:
• identifier;
• unique cellular subscriber identity;
• and the network address;
• and
• sending to the non-cellular telecommunications network, based on the generated mapping, the identifier in association with the network address.

A cellular telecommunications network comprising:

• a first network interface for communicating with a non-cellular telecommunications network;
• a second network interface for communicating with a User Equipment, UE, via the non-cellular telecommunications network;
• and
• a processor configured to:
• participate in establishing a network connection between the UE and the cellular telecommunications network via the non-cellular telecommunications network;
• obtain a:
• unique cellular subscriber identity, associated with the UE, for accessing the cellular telecommunications network;
• network address associated with the UE and for use with the non-cellular telecommunications network for the network connection;
• generate an identifier for identifying the UE to the non-cellular telecommunications network;
• generate a mapping between the:
• identifier;
• unique cellular subscriber identity;
• and the network address;
• and
• communicate, to the non-cellular telecommunications network via the first network interface, based on the generated mapping, the identifier, thereby to permit the non-cellular telecommunications network to associate the network address with the identifier.