A terminal device comprising a transceiver, a memory, and a processor is provided. The terminal device may send in a network, an IMS registration request to a network device in the network, and may start an IMS timer corresponding to the network. If the terminal device does not receive a registration accept message from the network device when the IMS timer expires, the terminal device deactivates the network. The network may be one of a first network and a second network, the network device may be one of a first network device and a second network device, and each of the first network and the second network corresponds to an IMS timer with a different duration. In this way, different waiting durations may be provided for IMS registration processes in different networks, to improve user communication experience.

A method for performing communication in a wireless communication system in includes establishing, by a network entity, a context of a user equipment (UE) in a network, receiving a message for registration request from the UE in a registered state, identifying that the UE is genuine by executing an authentication procedure with the UE, and in case that the UE is genuine, performing a deletion of the established context of the UE and a process of the registration request.

A method for performing communication in a wireless communication system in includes establishing, by a network entity, a context of a user equipment (UE) in a network, receiving a message for registration request from the UE in a registered state, identifying that the UE is genuine by executing an authentication procedure with the UE, and in case that the UE is genuine, performing a deletion of the established context of the UE and a process of the registration request.

Disclosed embodiments are related to various Radio Equipment implementations based on the European Union Radio Equipment Directive. Embodiments include implementations for safety and health, electromagnetic compatibility, and the efficient use of the radio spectrum, and cyber security including, inter alia, privacy protection and protection against fraud. Furthermore, additional aspects cover interoperability, access to emergency services, and compliance regarding the combination of Radio Equipment and software. Other embodiments may be described and/or claimed.

A network registration method for traffic steering and a device supporting the same is provided. An Access and mobility Management Function (AMF) receives a registration request message from a UE over a second non-3rd Generation Partnership Project (non-3GPP) access. The registration request message includes information related to access witching from a first non-3GPP access to the second non-3GPP access. Based on the registration request message, the AMF i) performs a normal registration procedure, and ii) delays a Unified Data Management (UDM) registration procedure. In addition, upon receiving, from a Session Management Function (SMF), information informing that the access switching from the first non-3GPP access to the second non-3GPP access is completed for the UE, the AMF performs an Access Network (AN) release procedure over the first non-3GPP access, performs the delayed UDM registration procedure.

A technique for enabling signaling message correlation in a telecommunication network is disclosed. A method implementation of the technique is performed by a network node in the telecommunication network and includes receiving a first signaling message as part of a signaling procedure among a plurality of network nodes in the telecommunication network, the first signaling message being transmitted using a first signaling protocol and including a correlation identifier being propagated along a message flow of the signaling procedure, and triggering transmitting a second signaling message as part of the signaling procedure using a second signaling protocol different from the first signaling protocol, wherein the correlation identifier of the first signaling message is incorporated into the second signaling message for further propagation.

A technique for enabling signaling message correlation in a telecommunication network is disclosed. A method implementation of the technique is performed by a network node in the telecommunication network and includes receiving a first signaling message as part of a signaling procedure among a plurality of network nodes in the telecommunication network, the first signaling message being transmitted using a first signaling protocol and including a correlation identifier being propagated along a message flow of the signaling procedure, and triggering transmitting a second signaling message as part of the signaling procedure using a second signaling protocol different from the first signaling protocol, wherein the correlation identifier of the first signaling message is incorporated into the second signaling message for further propagation.

A method comprising: determining, by a user equipment, that a non-closed access group cell is available to the user equipment in a public land mobile network, wherein the public land mobile network is identified by a public land mobile network identity and the user equipment is only allowed to access the public land mobile network via one or more closed access group cells; displaying the public land mobile network identity to a user; receiving user input selecting the public land mobile network identity; and transmitting a registration request to the public land mobile network identified by the public land mobile network identity.

A method comprising: determining, by a user equipment, that a non-closed access group cell is available to the user equipment in a public land mobile network, wherein the public land mobile network is identified by a public land mobile network identity and the user equipment is only allowed to access the public land mobile network via one or more closed access group cells; displaying the public land mobile network identity to a user; receiving user input selecting the public land mobile network identity; and transmitting a registration request to the public land mobile network identified by the public land mobile network identity.

A network search method includes presetting, by a terminal device, a Public Land Mobile Network (PLMN) and a networking mode associated with the PLMN, searching, by the terminal device based on a geographical location to obtain PLMN information of a current geographical location, determining, by the terminal device based on the preset PLMN and the networking mode associated with the PLMN, a current networking mode of the terminal device, and switching, by the terminal device, the networking mode based on a geographical location, signal strength, and a system message.