Abstract: In a communication system wherein a serving controller may be configured to support a first security mechanism and at least one other security mechanism. A request for registration is sent from a user equipment to the serving controller where after it is determined in a second controller that the user equipment supports another security mechanism than the first security mechanism. The second controller may then send to the serving controller an indication that another security mechanism than the first security mechanism is used by the user equipment. The serving controller then sends a challenge in accordance with the other security mechanism to the user equipment.

Abstract: A method in a communications system for handling responses to messages includes a step of sending a message from a first party to a second party. A response to the message is sent, with the response including at least one parameter in breach of a policy for a communication between the first party and the second party. A network controller detects that the response includes at least one parameter breaching the policy. The at least one parameter is modified to be consistent with the policy.

Abstract: A method of communication between a calling party in a first network and a called party in a second network is disclosed. The method comprises determining in the first network an address associated with the called party. The method also comprises determining, based on the address, if the called party is in a trusted network, and controlling the communication between the called party and the calling party in dependence on if the called party is in a trusted network.

Abstract: An apparatus and method routes a message via an IP Multimedia core Network Subsystem (IMS) system is disclosed. A message is received at an Interrogating Call Session Control Function (I-CSF). Address information is obtained for one of an application server, server or gateway for which the message is intended. The message is sent to the application server, server or gateway in accordance with the address information.

Abstract: A method in a communication system processes incoming requests at a controller entity. The method comprises the steps of registering a plurality of contact addresses for a user in a controller entity, receiving a request at the controller entity for a communication link to the user, querying a user information storage for information regarding a manner regarding how to handle the request, and processing the request in accordance with the information from the user information storage.

Abstract: This invention relates to a method for supporting a communication session of an user equipment, by means of a communication system that includes at least one entity between the user equipment and a node with which the user equipment is arranged to establish a session, the method including the steps of establishing a session between the user equipment and the node via the at least one entity, putting the session on hold, reserving resources for the session while the session is on hold, and resuming the session and distributing charging information.

Abstract: This invention relates to a method of communication comprising attempting to set up a session between a calling party and a called party via at least one entity; after a confirming response has been received from at least one of said called party, said calling party and said at least one entity, determining if said attempt to set up a session has failed; and preventing at least one of said calling party and said called party from being charged for said session.

Abstract: The invention proposes a method for controlling a network, wherein the networks offers services to registered users, the method comprising the steps of receiving (A1) a service request from network device (UE) of a user, checking whether the user is registered or not, and if the user is not registered, generating a response message including a warn information and sending (A2; B3 to B4) the response message to the network device (UE) of the user. The invention also proposes a corresponding network device. In this way, a user is informed that he has to register before he can obtain any services from the network.

Abstract: A communication system and a method wherein a subscription can be associated with a plurality of public and private identities are provided. According to one embodiment, the method includes the steps of storing in a user information storage information of the relations between the identities and of a control entity in which at least one of the public and private identities is registered, and allocating the control entity to a further registration based on the information stored in the user information storage.

Abstract: The invention relates to a service provisioning method in a communication system. In the method information regarding a communication control entity capable of servicing a user of the communication system is received at a first entity associated with the communication system from a storage entity. Based on said information, an originating request is then signalled from the first entity to the communication control entity.

Abstract: An apparatus and method requests a service by one party on behalf of another party. The method comprises the steps of requesting by the one party a service on behalf of the another party, the request including identity information of the another party, authenticating the one party and modifying the request to include identity information of the one party and permitting the one party to receive the service on behalf of another party, depending on the identity information of at least the another party.

Abstract: An apparatus and method of processing a service request in an IP multimedia core network is provided. The method includes the steps of receiving a service request initiated by a first user, for a second user, forwarding the received service request to a unit for processing the service, receiving a processing result from the processing unit, and determining, on the basis of the received processing result, whether the service request processing for the second user is to be stopped.

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 in a communication system wherein a user (1) is arranged to register with a control entity (22) comprises sending a message from the communication system to the user (1) requesting that the user re-register with said communication network. The user is caused to re-register with said network in response to said message.

Abstract: A security server for use in a telecommunications network is arranged to receive a message; determine whether the message is from a known source or an unknown source and, depending on the result of the determination, modify the message; and forward the message within the telecommunications network. A network processing element for use in a telecommunications network is arranged to receive a message from another network element; determine whether the message has been modified and, depending on the result of the determination, perform one or more security checks in respect of the message.

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 method and communication system are provided for authenticating a first entity (such as a mobile device) in the communications network. This may include transmitting a register message from the first entity to a second entity. An authentication challenge may be transmitted from the second entity to the first entity. The authentication challenge may include security association parameters within a header field. The response of the challenge may be transmitted from the first entity to the second entity. The response of the challenge may include security association parameters within a header field. A security association may be set up based on the security association parameters.

Abstract: The present invention is a system and method which provides authentication for data services for at least one UE (12) using common authentication information based upon information stored in a HSS (16) of a home network (20) of the at least one UE for multiple protocols. At least one proxy server (18) stores authentication information for each of the protocols which may be used to provide data services to the at least one UE. Authentication of the protocols available to the at least one UE uses the authentication information stored at the at least one proxy server obtained from the protocol used in the home network of the at least one UE.

Abstract: A method for selecting a time length of a security association (SA) between user equipment (UE) which transmits and receives communications and a control entity in a communication system in accordance with the invention, includes transmitting a registration message (SM1) from the user equipment to the control entity (P-CSCF) requesting registration of the user equipment with the control entity; after transmission of the registration message, setting the time length of the security association between the user equipment and the control entity to be equal to a registration time length set between the user equipment and the control entity during which registration of the user equipment with the control entity is valid; and transmitting the set time length of the security association to the user equipment as part of an acknowledgment message (SM10 or SM12) to the registration message to cause the security association to have a time equal to the registration timer length.