Abstract: A method for tracing a session or call in a network environment, comprising the step of transmitting a trace invocation from a control plane network element to another control pane network element or a user plane network element. According to a first aspect, a trace report is generated in the S-CSCF of the called party. This overcomes the lack of being able to provide detailed information about the interworking between the User Equipment (UE) and the IMS, in setting up IP multimedia sessions. According to a second aspect trace reports are generated in all the network functions involved in session setup.

Abstract: Performing an authentication of a subscriber in a communication system comprising at least two subsystems is disclosed, the authentication of the subscriber requiring authentications of the subscriber in any of the subsystems, the method performing a bundled subscriber authentication by using an authentication in a first one of the subsystems for an authentication in a second one of the subsystems.

Abstract: The present invention relates to a method, system, session control device and computer program product for maintaining a binding relationship in an address translation function (20) used for providing a translation between a first address used for addressing a device (10) from inside a data network and a second address used for addressing the device (10) from outside the data network. At a predetermined timing, a dedicated signaling message having at least an unknown portion not defined in the data network is generated, e.g. at a session control device (30), and transmitted to the device so as to initiate transmission of a predetermined response message via the address translation function (20). Thereby, the response message can easily be discriminated and does not require any substantial processing.

Abstract: The present invention is a method for service provisioning to a subscriber terminal (TE) having roamed from a first communication network (H-NW) to a second communication network (V-NW), each of said first and second networks comprises an access network (H-A-NW, V-A-NW; TL-NW) via which said subscriber terminal (TE) communicates with an associated core network (H-C-NW, V-C-NW), each of said core networks (H-C-NW, V-C-NW) being provided with at least one communication control entity (H-S-CSCF, V-S-CSCF) for performing, according to available services, communication control between the respective communication network and the terminal, and a database entity (H-SLS, V-SLS) keeping a record of available communication control entities in said core network of said communication network, said method comprising the steps of: accessing (S1), from said subscriber terminal (TE), the core network (V-C-NW) of said second communication network (V-NW), discovering (S2–S10) at least one communication control entity among the

Abstract: A method for a communication system and a communication system is disclosed. A user (1) can be provided with at least one registration at a first control entity (22). Said at least one registration is transferred to a second control entity (23) in response to another registration of the user to said second control entity. Any of the registrations may expiry in response to expiry of a timer.

Abstract: A method and a system for providing access to an IP multimedia subsystem (IMS) for a subscriber roaming in a visited communication network are described. A subscriber equipment determines that a visited network IMS is not accessible and sends a register message for registering to an IMS to a control entity in the home communication network of the subscriber. The control entity recognizes that the register message is received directly from a subscriber equipment, and an access entity for accessing the IMS of the home network is assigned. Then, the control entity sends a message to the subscriber equipment which message comprises the address of the access entity.

Abstract: A method for tracing a session or call in a network environment, comprising the step of transmitting a trace invocation from a control plane network element to another control pane network element or a user plane network element. According to a first aspect, a trace report is generated in the S-CSCF of the called party. This overcomes the lack of being able to provide detailed information about the interworking between the User Equipment (UE) and the IMS, in setting up IP multimedia sessions. According to a second aspect trace reports are generated in all the network functions involved in session setup.

Abstract: A technique for protecting location information of a subscriber in a mobile network may include forwarding a registration request from the subscriber to an S-CSCF including the subscriber's TA and then forwarding a location update from the S-CSCF to an HSS including the subscriber's TA. Upon the S-CSCF losing data, lost data may be restored to the S-CSCF from the data stored in the HSS. The HSS may store data in a non-volatile memory such as a hard disk drive. The technique may also include forwarding a registration request from the subscriber to an S-CSCF including the subscriber's TA and then forwarding a location update from the S-CSCF to an HSS and storing data in a non-volatile memory such as a hard disk drive in the S-CSCF so as to be protected against loss. Upon the S-CSCF losing data, lost data including the subscriber's TA may be restored to the S-CSCF from the data stored in the S-CSCF.