Abstract: The invention relates to a method of notifying an Application Function (AF) in a communications network of resource restrictions relating to a communication session. The network includes a Policy and Charging Rules Function (PCRF) for authorising and controlling flows of data in the session. In the method the AF sends an authorisation request to the PCRF for establishing the communication session. The authorisation request includes an indication that the AF is to be notified of resource restrictions for the data flows in the session. The PCRF notifies the AF of the resource restrictions.

Abstract: The invention relates to a method of notifying an Application Function (AF) in a communications network of resource restrictions relating to a communication session. The network includes a Policy and Charging Rules Function (PCRF) for authorising and controlling flows of data in the session. In the method the AF sends an authorisation request to the PCRF for establishing the communication session. The authorisation request includes an indication that the AF is to be notified of resource restrictions for the data flows in the session. The PCRF notifies the AF of the resource restrictions.

Abstract: Mechanisms are disclosed for the provision and use of executable logic in user equipment during an IMS call/session. Application program logic is provided from a first User Equipment, UE, to a second UE communicating with each other. A first application in the first UE is executed to generate program logic, or a link to the program logic of a second application. The generated program logic, or link is sent to the second UE. A UE receiving a signal that includes program logic, or a link to program logic of the application, installs the program logic, or follows the link to download and install the program logic in the UE. The UE then executes the program logic to run the application.

Abstract: A system, method, and Proxy Call/Session Control Function (P-CSCF) for transporting signaling connectivity status information relating to a signaling connection between a terminal and the P-CSCF in an IP Multimedia Subsystem (IMS) network. In one embodiment, when the P-CSCF detects that the connectivity status has changed, the P-CSCF sends a SIP request such as a REGISTER request to a Serving CSCF (S-CSCF) indicating the new status. Alternatively, the registration event package of the terminal may be extended to include the connectivity status, and the P-CSCF then sends the status in a PUBLISH request. In an alternative embodiment, the P-CSCF maintains a new SIP event package. The S-CSCF subscribes to the SIP event package and the P-CSCF notifies the S-CSCF upon a change of connectivity status.

Abstract: The invention relates to a method of establishing a session between client user terminals accessing IP Multimedia Subsystem, IMS, networks. At least one of the IMS networks implements the use of Quality of Service, QoS, preconditions, and at least one of the client user terminals does not use QoS preconditions. The method includes receiving, at an inter-working function, IWF located in one of the IMS networks, an IMS session initiation request originated by an originating client, the request indicating a terminating client for the session. A decision is made, based on the session initiation request, that one of the originating client and the terminating client is not using QoS preconditions. A set of QoS preconditions is inserted into a procedure for establishing the IMS session on behalf of the client that is not using QoS preconditions. Session establishment is completed only after QoS resources complying with the set of QoS preconditions have been established.

Abstract: A generic method is described for storing data in the HSS (2) by the S-CSCF (1) of an IMS. When a SIP message containing new information relating to an IMPI/IMPU pair is received by the S-CSCF (1), a data package is created for storage at the HSS (2), containing the new information. An SAR command is sent to the HSS (2) containing an AVP including an instruction to the HSS (2) and the new data package. In one aspect a unique data package is controlled by the S-CSCF (1). When new information relating to the IMPI/IMPU is received in a SIP message, this is added to any previously sent data package to create a new data package. In another aspect the HSS (2) controls a unique data package, returning the data package to the S-CSCF (1) to be amended if necessary. In another aspect separate data packages are used.

Abstract: A method is provided for facilitating recovery from the failure of a P-CSCF within an IP multimedia Subsystem network. A gateway, such as a GGSN, monitors signals arriving at the gateway from the P-CSCF and provides an indication if the monitored signals become unacceptable, for example because of an interruption in the signals. The gateway responds by signalling the unavailability of the P-CSCF to user equipment, which was associated with the P-CSCF during a previous registration with the IMS network. In response, for example, the user equipment affected by the failure may request re-registration with the IMS network using a different available P-CSCF.

Abstract: An originating P-CSCF node receives a SIP INVITE request from first user equipment (UE) that originates a call to a second UE. If a relay candidate address for the first UE is not present in the SIP INVITE request, the SIP INVITE request is modified to include a first address provided by an originating IMS-AGW node as a relay candidate for the first UE and forwarded to the second UE. The originating P-CSDF node receives a SIP INVITE response message from the second UE in response to the SIP INVITE request. If a relay candidate address for the second UE is not present in the SIP INVITE response, the SIP invite response is modified to include a second address provided by an originating IMS-AGW node as a relay candidate for the second UE and forwarded t the first UE. The address information is used by both UEs in ICE operations.

Abstract: A method of operating an Internet Protocol Multimedia Subsystem (IMS) network having a plurality of user interfaces. A terminal agent is interposed between a plurality of Session Initiation Protocol (SIP) User Agents and a Serving Call/Session Control Function (S-CSCF) of the IMS network. The terminal agent registers its contact address with the S-CSCF on behalf of the plurality of SIP User Agents and emulates a single SIP User Agent to the S-CSCF.

Abstract: Methods and apparatus facilitate recovery of an IMS in which an S-CSCF has suffered a restart (after a failure, software upgrade, or other reasons). One or more of first and second methods comprise submitting, from the S-CSCF towards a HSS, contact data required by the S-CSCF to contact a given subscriber, or to contact a proxy server through which the subscriber is accessible; storing the contact data at the HSS; and providing from the HSS towards an IMS entity, which may be previously assigned S-CSCF or a new S-CSCF, contact information elements selectable from the contact data.

Abstract: A method of enabling users of a third party Internet service, who are not necessarily subscribers of an IP Multimedia Subsystem, IMS, network, to access services provided by the IMS network. The method comprises registering a user with said third party Internet service via the Internet using an Internet service identity of the user, and sending to the user, from said third party Internet service and via the Internet, IMS network access information. The access information is then used to register the user with the IMS network, wherein, following IMS registration, the user is able to access IMS network services.

Abstract: A protocol conversion gateway and a method therein for enabling a client, which client does not support a Session Initiation Protocol (SIP) transport protocol, to communicate with a SIP proxy are provided. The method comprises receiving a first SIP message, over a non-standard SIP transport protocol, from the client. The method further comprises inserting a SIP address of the protocol conversion gateway in at least one header of the received SIP message, and sending the SIP message to the SIP proxy over a standard SIP transport protocol.

Abstract: A server, computer readable medium and method for accessing buddy data related to a first user (presentity) that is connected to a START communication network that includes a server, the data being accessed by a second user (watcher) connected to the communication network. The method including storing, at a server, information associated with a plurality of users associated with the presentity as the buddy data, receiving, at the server, a request from a watcher for buddy data of the presentity, authorizing, at least in part by the server, the request for buddy data, and transmitting, by the server, the buddy information to the watcher.

Abstract: A method, application server, and Serving Call/Session Control Function (S-CSCF) for allocating a SIP Application Server to a subscriber in an IP Multimedia Subsystem. A Home Subscriber Server (HSS) identifies for the subscriber, a set of provisioned initial filter criteria, which contains at least one generic SIP Application Server identity. The HSS sends the filter criteria to an S-CSCF allocated to the subscriber. The S-CSCF resolves the generic SIP Application Server identity into a plurality of application server addresses, with one of the addresses being allocated to the subscriber for use in provisioning a service to the subscriber. The S-CSCF caches the address allocated to the subscriber for subsequent use.

Abstract: A method of controlling access to services of an IP Multimedia Subsystem (IMS) by a user based upon the user's location. In response to a user requesting access to a service, information identifying the user's location is provided to the IMS. Within the IMS, the provided information is compared with authorization information stored in a database. The authorization information includes information identifying prohibited and/or allowed access locations. Dependent upon the result of the comparison, access to the IMS services is allowed or denied.

Abstract: A method of evaluating Initial Filter Criteria (IFC) at a terminating Serving Call Session Control Function (S-CSCF) in an IP Multimedia Subsystem network. Upon receiving a Session Initiation Protocol (SIP) message containing a destination Uniform Resource Identifier (URI), the S-CSCF applies an Initial Filter Criterion to the message, sends the message to an Application Server (AS), and suspends further IFC evaluation. When a return message is received from the AS, the S-CSCF determines whether the AS changed the URI. If so, the S-CSCF makes a determination of whether to resume IFC evaluation. If the AS did not change the URI, the S-CSCF resumes IFC evaluation.

Abstract: A Home Subscriber Server for handling IP Multimedia Subsystem subscriptions comprises means for maintaining associations between public user identities and Service Profiles, where two or more public user identities can be associated with a common Service Profile, and means for identifying to a network node all public user identities that are associated with a common Service Profile.

Abstract: A Home Subscriber Server for handling IP Multimedia Subsystem subscriptions comprises means for maintaining associations between public user identities and Service Profiles, where two or more public user identities can be associated with a common Service Profile, and means for identifying to a network node all public user identities that are associated with a common Service Profile.

Abstract: A method and apparatus for registering a mobile node such as a User Equipment (UE) of a UMTS telecommunications network with a subsystem of the network such as an IP Multimedia Subsystem (IMS). A Policy and Charging Rules Function (PCRF) node provides policy and charging rules, and a Gateway GPRS Support Node (GGSN) enforces the rules for traffic flows. The UE sends a registration request to the GGSN, which selects a PCRF. When a Proxy Call Session Control Function (P-CSCF) receives the registration request, the P-CSCF selects a candidate PCRF and validates the selection. If the candidate PCRF is the PCRF selected by the GGSN, the registration is successful. If not, the P-CSCF may select another PCRF and repeat the validation process.

Abstract: A method is provided for use in a push to talk or conferencing type service involving a terminal and a controller, comprising, in response to the controller deciding to grant a talk request received from the terminal, sending to the terminal an indication of an allowed talk time for a granted talk burst, the indication being for use at the terminal to monitor the remaining allowed talk time during the granted talk burst. There is also provided a method for use in a push to talk or conferencing type service involving a terminal and a controller, comprising, in response to the controller deciding to grant a talk request received from the terminal, monitoring the remaining allowed talk time at the controller using an allowed talk timer and starting the allowed talk timer at the controller in response to receipt of talk burst data from the terminal.