A method performed by a first node (111) managing a P-CSCF in a first communications network (101). The method is for handling identification of a second communications network (201). One of the communications networks is a home network and the other is a visited network. The first node (111) obtains (701) a unique identifier uniquely identifying the second communications network (201) in a plurality of networks (200) sharing a Mobile Network identifier. The unique identifier is based on: a) an MCC and an MNC, corresponding to a shared PLMN identifier, and b) a subscriber identifier corresponding to the second network (201). The first node (111) also processes (702) provision of an IMS service across the communications networks, to a device (230) operating in the visited network, based on the identifier. The processing (702) comprises, in the home network, one of: i) application of a policy or rule, and ii) routing a communication to a S-CSCF.Publ.

A method performed by a first node (111) managing a P-CSCF in a first communications network (101). The method is for handling identification of a second communications network (201). One of the communications networks is a home network and the other is a visited network. The first node (111) obtains (701) a unique identifier uniquely identifying the second communications network (201) in a plurality of networks (200) sharing a Mobile Network identifier. The unique identifier is based on: a) an MCC and an MNC, corresponding to a shared PLMN identifier, and b) a subscriber identifier corresponding to the second network (201). The first node (111) also processes (702) provision of an IMS service across the communications networks, to a device (230) operating in the visited network, based on the identifier. The processing (702) comprises, in the home network, one of: i) application of a policy or rule, and ii) routing a communication to a S-CSCF.Publ.

Techniques and systems for recovering a communication session from a dedicated bearer failure are disclosed. For example, a P-CSCF node can determine that a dedicated bearer associated with a communication session has failed, and, in response, send a SIP message to a UE associated with the communication session, the SIP message causing the UE to refrain from sending SIP requests using a SIP INVITE method. The process may further include identifying a first network node associated with an identifier of the UE, the first network node comprising one of a PGW or a SMF, and sending an instruction to the first network node to dissociate the dedicated bearer from the communication session. This causes a new attach procedure to be performed by the UE to recover the session without session failure.

Techniques and systems for recovering a communication session from a dedicated bearer failure are disclosed. For example, a P-CSCF node can determine that a dedicated bearer associated with a communication session has failed, and, in response, send a SIP message to a UE associated with the communication session, the SIP message causing the UE to refrain from sending SIP requests using a SIP INVITE method. The process may further include identifying a first network node associated with an identifier of the UE, the first network node comprising one of a PGW or a SMF, and sending an instruction to the first network node to dissociate the dedicated bearer from the communication session. This causes a new attach procedure to be performed by the UE to recover the session without session failure.

This disclosure is related to a procedure to provide emergency services support for a UE which does not have a valid subscription for the serving PLMN. This disclosure more specifically provides procedure to support IMS emergency call or eCall support for a UE which is in limited state on a E-UTRA cell is connected to both EPC and 5GCN.

The disclosure relates to methods and system for handling immersive services with feature tags in an 3GPP IP multimedia subsystem (IMS) and 3GPP mission critical services (MCX). A user equipment uses the media tags, feature tags with unique IMS communication service identifier (ICSI) and IMS application reference identifier (IARI) to communicate with the IMS network for determining the immersive services in the communication. Accordingly, a method includes: performing, a registration with a network for handling immersive call services based on feature tags included in a session initiation protocol (SIP) REGISTER request; determining whether the network provides a provision for the handling of immersive call services based on an SIP REGISTER response; and sending an SIP INVITE request including feature tags to a second client device via the network based on determining that the network provides the provision of handling immersive media streams. Thus, the immersive call is established by the first client device with the second client device.

A method of managing access to a plurality of Packet Switched (PS) networks of a wireless communication apparatus including a plurality of Subscriber Identity Modules (SIMs) includes obtaining first information indicating data service-related preferences for the plurality of SIMs, selecting at least one SIM necessary for accessing each of the plurality of PS networks from among the plurality of SIMs, based on the first information and second information indicating a wireless network capable of being provided by an operator corresponding to each of the plurality of SIMs, and accessing each of the plurality of PS networks by using the selected at least one SIM.

A method of managing access to a plurality of Packet Switched (PS) networks of a wireless communication apparatus including a plurality of Subscriber Identity Modules (SIMs) includes obtaining first information indicating data service-related preferences for the plurality of SIMs, selecting at least one SIM necessary for accessing each of the plurality of PS networks from among the plurality of SIMs, based on the first information and second information indicating a wireless network capable of being provided by an operator corresponding to each of the plurality of SIMs, and accessing each of the plurality of PS networks by using the selected at least one SIM.

It is provided a method, comprising monitoring, for each of plural attempts of a web identity to register for an internet protocol multimedia service, if the respective attempt is received; generating, for each of the plural attempts if the respective attempt is received, a respective private user identification based on the web identity and a respective distinguishing identifier, wherein probability that two of the private user identifications have a same value is less than a predefined limit; providing the respective private user identification in response to the respective attempt.

Various embodiments of the present technology allow multi-realm support at US-CSCF to IMS by the same I/S-CSCF nodes. Some embodiments allow for a registration message to be received from an IMS client. The registration message can be used to establish, through an Internet Protocol Multimedia Subsystem (IMS) core network, a service between a first endpoint associated with a first realm and a second endpoint associated with a second, different realm. The registration message can be translated so that the second endpoint believes the first endpoint is associated with the second realm before being transmitted to the second endpoint. Upon receiving a successful IMS registration message from the IMS core network, a binding can be created between the first endpoint and the second endpoint.