Systems and methods for providing secure communication between an inmate and an outside user are disclosed. In various aspects, account information of both the user and the inmate is stored. A message transmission is received from a first device that includes a header portion and an encrypted payload portion. The system verifies that confidential communication between the inmate and the outside user is permitted based on the header portion and the stored account information. Once verified, the message is transmitted to a second device without decrypting the payload portion of the message.

Embodiments of the present application provide methods for checking UE capability match, an AMF, a base station, and a storage medium. The method includes: determining to send a UE capability match request to a base station during a registration procedure initiated by the UE; sending a request for setting up a UE's access stratum (AS) security context to the base station, and sending the UE capability match request to the base station after it is determined that the base station completes setup of the AS security context; receiving a UE capability match acknowledgement returned from the base station. By the method according to the embodiment of the application, the problem that the base station does not respond to the UE capability match process requested by the AMF, which results in that the AMF cannot issue an indication of IMS voice over PS session to the UE during the registration process, can be avoided, and thus the UE can normally obtain IMS voice service.

This disclosure describes a user equipment device (UE). The UE includes one or more antennas; one or more radios configured to perform cellular communication using a plurality of radio access technologies (RATs) that support voice over an Internet protocol (IP) multimedia subsystem (IMS); and one or more processors coupled to the one or more radios. The one or more processors are configured to cause the UE to perform operations including: sending, to a communications network associated with a first RAT of the plurality of RATs, a first request for IMS registration, wherein the UE is camped on a first cell of the first RAT; determining, based on an IMS rejection failure, that the IMS registration failure is due to a temporary radio failure; and responsively attempting to perform the IMS registration on at least one other cell of the first RAT.

This disclosure describes a user equipment device (UE). The UE includes one or more antennas; one or more radios configured to perform cellular communication using a plurality of radio access technologies (RATs) that support voice over an Internet protocol (IP) multimedia subsystem (IMS); and one or more processors coupled to the one or more radios. The one or more processors are configured to cause the UE to perform operations including: sending, to a communications network associated with a first RAT of the plurality of RATs, a first request for IMS registration, wherein the UE is camped on a first cell of the first RAT; determining, based on an IMS rejection failure, that the IMS registration failure is due to a temporary radio failure; and responsively attempting to perform the IMS registration on at least one other cell of the first RAT.

This disclosure describes a user equipment device (UE). The UE includes one or more antennas; one or more radios, where each of the radios is configured to perform cellular communication using a plurality of radio access technologies (RATs) that support voice over an Internet protocol (IP) multimedia subsystem (IMS); one or more processors coupled to the one or more radios, where the one or more processors are configured to cause the UE to perform operations including: sending, via a first RAT, a first request for IMS registration to an IMS server; receiving, from the IMS server, an IMS rejection message indicating failure of the IMS registration; determining, based on the IMS rejection message, that the IMS registration failure is temporary; responsively re-attempting IMS registration with the IMS server; and determining to camp on the first RAT in response to receiving an IMS acceptance message from the IMS server.

This disclosure describes a user equipment device (UE). The UE includes one or more antennas; one or more radios, where each of the radios is configured to perform cellular communication using a plurality of radio access technologies (RATs) that support voice over an Internet protocol (IP) multimedia subsystem (IMS); one or more processors coupled to the one or more radios, where the one or more processors are configured to cause the UE to perform operations including: sending, via a first RAT, a first request for IMS registration to an IMS server; receiving, from the IMS server, an IMS rejection message indicating failure of the IMS registration; determining, based on the IMS rejection message, that the IMS registration failure is temporary; responsively re-attempting IMS registration with the IMS server; and determining to camp on the first RAT in response to receiving an IMS acceptance message from the IMS server.

This disclosure describes a communication system associated with a radio access technology (RAT). The communication system includes an Internet protocol (IP) multimedia subsystem (IMS) server, and one or more processors configured to perform operations. The operations include receiving, from a user equipment device (UE) camped on the RAT, a request for IMS Packet Data Unit (PDU) establishment or IMS session initiation protocol (SIP) registration; sending to the UE a rejection message associated with the SIP registration or the IMS PDU establishment; receiving, from the UE, an IMS failure message that comprises an IMS failure cause; determining, based on the IMS failure message, whether the IMS failure cause is temporary or permanent; and responsive to determining that the IMS failure is temporary, temporarily disabling the RAT for the UE.

The disclosure provides a method for assisting an unregistered user device to access private network services and a communication system. The method includes steps as follows. A request to access a private service of a private network is sent by a user device. In response to determining that the user device not registered on the private network wants to access the private service, the user device is assisted to obtain a temporary user profile by a mobile edge computing server through an emergency type attachment procedure. In response to determining that the user device is registered on the private network through the emergency type attachment procedure, a regular attachment procedure is executed by the user device based on the temporary user profile. In response to determining that the user device executes the regular attachment procedure, the mobile edge computing server provides the user device with the private service.

Apparatuses, methods, and systems are disclosed for establishing a connection with a dual registered device. One method includes receiving a first request to establish an internet protocol multimedia subsystem session with a first device, wherein the first device is dual registered to: a first network access supporting 5G core network connectivity; and a second network access supporting evolved packet core network connectivity and circuit switched network connectivity, wherein the first device has connectivity to an internet protocol multimedia subsystem via either the first network access or the second network access. The method includes determining first information corresponding to a network access connectivity selected from the first network access and the second network access through which the first device has internet protocol connectivity with the internet protocol multimedia subsystem. The method includes transmitting a second request to a first network function to retrieve second information.

Described herein are techniques, devices, and systems for handling Session Initiation Protocol (SIP) messages with malformed header fields. A communication device that receives a SIP message from an additional communication device may identify one or more identified header fields of a plurality of first header fields in a message header of the SIP message that correspond to (e.g., match) one or more second header fields in a list of second header fields accessible to the communication device. If the communication device determines that the one or more identified header fields are not malformed, the communication device may process the SIP message without regard to remaining header fields in the message header. If, however, the communication device determines that at least one identified header field of the one or more identified header fields is malformed, the communication device may reject the SIP message.