Abstract: A communication terminal (10) according to the present disclosure includes: a control unit (12) configured to, in a case of a movement from a communication area formed by the 5GS to a communication area formed by the EPS or a movement from a communication area formed by the EPS to a communication area formed by the 5GS, determine whether or not a communication system forming a communication area at a movement destination can satisfy requirements of services; and a communication unit (11) configured to, when it is determined that the communication system forming the communication area at the movement destination can satisfy the requirements of the services, send a connection request message to the communication system forming the communication area at the movement destination.

Abstract: A communication terminal capable of preventing a reduction in security level that is caused at the time of establishing multiple connections via 3GPP Access and Non-3GPP Access. A communication terminal according to the present disclosure includes: a communication unit configured to communicate with gateway devices disposed in a preceding stage of a core network device via an Untrusted Non-3GPP Access; and a key derivation unit configured to derive a second security key used for security processing of a message transmitted using a defined protocol with the gateway device, from a first security key used for security processing of a message transmitted using a defined protocol with the core network device.

Abstract: Provided is an authentication device capable of generating a master key suited to a UE in a 5GS. The authentication device (10) includes a communication unit (11) configured to, in registration processing of user equipment (UE), acquire UE key derivation function (KDF) capabilities indicating a pseudo random function supported by the UE, a selection unit (12) configured to select a pseudo random function used for generation of a master key related to the UE by use of the UE KDF capabilities, and a key generation unit (13) configured to generate a master key related to the UE by use of the selected pseudo random function.

Abstract: A communication terminal (10) includes control means for generating a subscription concealed identifier (SUCI) including a subscription permanent identifier (SUPI) concealed using a predetermined protection scheme, and a protection scheme identifier identifying the protection scheme, and transmission means for sending the SUCI to a first network apparatus during a registration procedure, the SUCI being sent for a second network apparatus to de-conceal the SUPI from the SUCI based on the protection scheme used to generate the SUCI.

Abstract: A method for integrity protection scheme by a mobile communication device or a core network entity according to a first exemplary aspect of the present disclosure includes configuring settings and parameters for integrity protection for user data with another party; receiving user plane data from the other party, calculating Message Authentication Code for Integrity (MAC-I) for a part of the data and checking integrity of the part of the data.

Abstract: A method for integrity protection scheme by a mobile communication device or a core network entity according to a first exemplary aspect of the present disclosure includes configuring settings and parameters for integrity protection for user data with another party; receiving user plane data from the other party, calculating Message Authentication Code for Integrity (MAC-I) for a part of the data and checking integrity of the part of the data.

Abstract: A communication terminal (10) according to the present disclosure includes: a control unit (12) configured to, in a case of a movement from a communication area formed by the 5GS to a communication area formed by the EPS or a movement from a communication area formed by the EPS to a communication area formed by the 5GS, determine whether or not a communication system forming a communication area at a movement destination can satisfy requirements of services; and a communication unit (11) configured to, when it is determined that the communication system forming the communication area at the movement destination can satisfy the requirements of the services, send a connection request message to the communication system forming the communication area at the movement destination.

Abstract: Provided is an authentication device capable of generating a master key suited to a UE in a 5GS. The authentication device (10) includes a communication unit (11) configured to, in registration processing of user equipment (UE), acquire UE key derivation function (KDF) capabilities indicating a pseudo random function supported by the UE, a selection unit (12) configured to select a pseudo random function used for generation of a master key related to the UE by use of the UE KDF capabilities, and a key generation unit (13) configured to generate a master key related to the UE by use of the selected pseudo random function.

Abstract: A communication terminal (10) includes control means for generating a subscription concealed identifier (SUCI) including a subscription permanent identifier (SUPI) concealed using a predetermined protection scheme, and a protection scheme identifier identifying the protection scheme, and transmission means for sending the SUCI to a first network apparatus during a registration procedure, the SUCI being sent for a second network apparatus to de-conceal the SUPI from the SUCI based on the protection scheme used to generate the SUCI.

Abstract: A communication terminal (10) according to the present disclosure includes: a control unit (12) configured to, in a case of a movement from a communication area formed by the 5GS to a communication area formed by the EPS or a movement from a communication area formed by the EPS to a communication area formed by the 5GS, determine whether or not a communication system forming a communication area at a movement destination can satisfy requirements of services; and a communication unit (11) configured to, when it is determined that the communication system forming the communication area at the movement destination can satisfy the requirements of the services, send a connection request message to the communication system forming the communication area at the movement destination.

Abstract: Provided is an authentication device capable of generating a master key suited to a UE in a 5GS. The authentication device (10) includes a communication unit (11) configured to, in registration processing of user equipment (UE), acquire UE key derivation function (KDF) capabilities indicating a pseudo random function supported by the UE, a selection unit (12) configured to select a pseudo random function used for generation of a master key related to the UE by use of the UE KDF capabilities, and a key generation unit (13) configured to generate a master key related to the UE by use of the selected pseudo random function.

Abstract: A communication terminal (10) includes control means for generating a subscription concealed identifier (SUCI) including a subscription permanent identifier (SUPI) concealed using a predetermined protection scheme, and a protection scheme identifier identifying the protection scheme, and transmission means for sending the SUCI to a first network apparatus during a registration procedure, the SUCI being sent for a second network apparatus to de-conceal the SUPI from the SUCI based on the protection scheme used to generate the SUCI.

Abstract: Methods for (i) finding/discovering the right UDM instances and (ii) ensuring the UDM instance security are provided. The method for (i), includes the steps of: (i-1) pre-provisioning of UDM instance discovery information/parameters to the UE/USIM, (i-2) sending the UDM instance discovery related parameters to a core network element, and (i-3) discovering the right UDM instance at the core network element based on the discovery parameters and related routing information either at the UDM consumer/NRF. The method for (ii) includes the steps of: (ii-1) Secured choice of parameter for UDM instance discovery (e.g. UDM instance identifier) to the core network element and (ii-2) the secured UDM instance identifier generation and management at the UDM to prevent attack on UDM instances. Also a method to identify the cleartext IMSI/SUPI is provided for the re-authentication scenario along with the relevant procedures.

Abstract: The present disclosure relates to authentication methods supported by the User Equipment (UE) to the core network and authentication method (selected by the core network) to the UE. These can be used for negotiating any primary or secondary (or any) authentication method and are applicable when multiple authentication methods are supported at the UE and the network (authentication server). Further, the present disclosure also offers security solution to prevent modification or tampering of the parameters in the mechanisms in order to prevent attacks such as bidding-down, Denial of Service (DoS) and Man-In-The-Middle (MITM).

Abstract: A communication terminal (10) includes control means for generating a subscription concealed identifier (SUCI) including a subscription permanent identifier (SUPI) concealed using a predetermined protection scheme, and a protection scheme identifier identifying the protection scheme, and transmission means for sending the SUCI to a first network apparatus during a registration procedure, the SUCI being sent for a second network apparatus to de-conceal the SUPI from the SUCI based on the protection scheme used to generate the SUCI.

Abstract: A method for integrity protection scheme by a mobile communication device or a core network entity according to a first exemplary aspect of the present disclosure includes configuring settings and parameters for integrity protection for user data with another party; receiving user plane data from the other party, calculating Message Authentication Code for Integrity (MAC-I) for a part of the data and checking integrity of the part of the data.

Abstract: The present disclosure relates to secure provisioning of UE mobility restriction by extending neighbour relation tables to include mobility restrictions in addition to neighbour cell information and sending neighbour cell restriction information (per UE) to the UE, gNB, UE and gNB. The present invention also provides a method and apparatus and a system for mapping mobility restrictions with TA list and sending the TA list along with the Handover Restriction List during handover.

Abstract: The present disclosure aims to provide a communication system capable of achieving advanced security in a 5G communication system. The communication system according to the present disclosure includes: a communication terminal (10); an Access and Mobility Management (AMF) entity (20) configured to execute Mobility Management (MM) processing regarding the communication terminal (10); and a Session Management Function (SMF) entity (30) configured to execute Session Management (SM) processing regarding the communication terminal (10), in which the communication terminal (10) sends an MM message used in the MM processing, a first security key having been applied to the MM message, between the communication terminal and the AMF entity (20), and sends an SM message used in the SM processing, a second security key having been applied to the SM message, between the communication terminal and the SMF entity (30) via the AMF entity (20).

Abstract: An object is to provide a communication terminal capable of using a newly-generated network slice or service. A communication terminal (10) according to the present disclosure includes a communication unit (11) configured to receive a parameter related to SM-NSSAI (Session Management-Network Slice Selection Assistance Information) from a core network when subscriber information of the communication terminal itself managed in the core network or a location of the communication terminal itself is changed, and a control unit (12) configured to update NSSAI by using the parameter related to the SM-NSSAI, the NSSAI being managed to select a network slice.

Abstract: A communication terminal (10) according to the present disclosure includes: a control unit (12) configured to, in a case of a movement from a communication area formed by the 5GS to a communication area formed by the EPS or a movement from a communication area formed by the EPS to a communication area formed by the 5GS, determine whether or not a communication system forming a communication area at a movement destination can satisfy requirements of services; and a communication unit (11) configured to, when it is determined that the communication system forming the communication area at the movement destination can satisfy the requirements of the services, send a connection request message to the communication system forming the communication area at the movement destination.