Apparatuses, methods, and systems are disclosed for determining mobile network policy freshness. One method includes accessing a first policy associated with a first mobile network, a first policy identifier, and a freshness parameter. The method includes determining, based on the freshness parameter, whether the first policy is fresh. The method includes transmitting a registration message to a second mobile network. The registration message includes the first policy identifier in response to determining that the first policy is not fresh.

Selecting a serving session control node in an Internet Protocol, IP, Multimedia Subsystem, IMS, telecommunication network, for a User Equipment. The method includes receiving, by an interrogating session control node, a Session Initiation Protocol, SIP register message for registering said UE in said IMS telecommunication network, the SIP register message has a UE capability feature mappable to a UE initiated server capability for the serving session control node, transmitting, by the interrogating session control node, to a Home Subscriber Server, a user authorization request message comprising the UE capability feature, receiving, by the interrogating session control node, from the Home Subscriber Server, a user authorization answer message including one or more UE initiated server capabilities for a serving session control node, selecting, by the interrogating session control node, a serving session control node based on the one or more received UE initiated server capabilities in the user authorization answer message.

Selecting a serving session control node in an Internet Protocol, IP, Multimedia Subsystem, IMS, telecommunication network, for a User Equipment. The method includes receiving, by an interrogating session control node, a Session Initiation Protocol, SIP register message for registering said UE in said IMS telecommunication network, the SIP register message has a UE capability feature mappable to a UE initiated server capability for the serving session control node, transmitting, by the interrogating session control node, to a Home Subscriber Server, a user authorization request message comprising the UE capability feature, receiving, by the interrogating session control node, from the Home Subscriber Server, a user authorization answer message including one or more UE initiated server capabilities for a serving session control node, selecting, by the interrogating session control node, a serving session control node based on the one or more received UE initiated server capabilities in the user authorization answer message.

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 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.

In an example embodiment, a solution that allows a PBX to utilize bridged mobile or desktop applications for collaboration and softphone use is provided. The solution works in conjunction with existing hardwired PBX devices without requiring additional hardware such as an edge router to be integrated with the PBX hardware. Incoming calls are able to ring a user's hardwired device, such as a desk phone at an office, while simultaneously ring mobile device or desktop applications (apps). App users can place outbound PSTN calls and dial PBX extensions just as if they were using their hardwired device. Additionally, PSTN services are utilized from the existing PBX rather than bypassing the existing PBX, which makes tracking and billing more straightforward. A Session Initiation Protocol (SIP) tie trunk is used between the existing PBX and a software bridge controller.

In an example embodiment, a solution that allows a PBX to utilize bridged mobile or desktop applications for collaboration and softphone use is provided. The solution works in conjunction with existing hardwired PBX devices without requiring additional hardware such as an edge router to be integrated with the PBX hardware. Incoming calls are able to ring a user's hardwired device, such as a desk phone at an office, while simultaneously ring mobile device or desktop applications (apps). App users can place outbound PSTN calls and dial PBX extensions just as if they were using their hardwired device. Additionally, PSTN services are utilized from the existing PBX rather than bypassing the existing PBX, which makes tracking and billing more straightforward. A Session Initiation Protocol (SIP) tie trunk is used between the existing PBX and a software bridge controller.

In a LTE network user devices can access voice application service via Voice over LTE (VoLTE) and Voice over WiFi (VoWiFi). To detect faults in the data link associated with an evolved packet data gateway for providing access by the user device to the LTE network from a non-trusted network which will affect VoWiFi capability, a packet data gateway monitors the status of ePDG and if a fault is detected, the user device is notified that it should connect to voice services via VoLTE.

In a LTE network user devices can access voice application service via Voice over LTE (VoLTE) and Voice over WiFi (VoWiFi). To detect faults in the data link associated with an evolved packet data gateway for providing access by the user device to the LTE network from a non-trusted network which will affect VoWiFi capability, a packet data gateway monitors the status of ePDG and if a fault is detected, the user device is notified that it should connect to voice services via VoLTE.

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.