Methods, apparatuses, computer programs and carriers for security management before handover from 5G to 4G system
AssigneeTelefonaktiebolaget LM Ericsson (publ)
InventorsMonica Wifvesson, Noamen Ben Henda, Christine Jost, Vesa Lehtovirta
Life of this patent
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Abstract
A key management is provided that enables security activation before handing over a user equipment from a source 5G wireless communication system, i.e., a Next Generation System (NGS), to a target 4G wireless communication system, i.e., a Evolved Packet System (EPS)/Long Term Evolution (LTE). The key management achieves backward security, i.e., prevents the target 4G wireless communication system from getting knowledge of 5G security information used in the source 5G wireless communication system.
Claims15
A host computer, comprising:
- processing circuitry configured to provide user data;
- and
- a communication interface configured to forward the user data to a cellular network for transmission to a user equipment (UE), wherein the cellular network comprises a key management arrangement configured to perform operations comprising:
- deriving a first 4G-master key based on a 5G key, KAMF, available at an Access and Mobility management Function (AMF) constituting a core network node supporting mobility management of a source 5G wireless communication system, and on a 5G-freshness parameter;
- forwarding the first 4G-master key to a target mobility managing entity (MME) of a target 4G wireless communication system for enabling deriving a second 4G-master key based on the first 4G-master key and a 4G-freshness parameter;
- and
- forwarding the 5G-freshness parameter to the user equipment for enabling deriving the first 4G-master key based on the 5G key, KAMF, and the 5G-freshness parameter and deriving the second 4G-master key based on the first 4G-master key and the 4G-freshness parameter.
A non-transitory computer readable medium comprising instructions that, when executed by a processor in a host computer of a communication system, cause the host computer to perform operations comprising:
- providing user data;
- and
- forwarding the user data to a cellular network, via a communication interface, for transmission to a user equipment (UE), wherein the cellular network comprises a key management arrangement configured to perform operations comprising:
- deriving a first 4G-master key based on a 5G key, KAMF, available at an Access and Mobility management Function (AMF) constituting a core network node supporting mobility management of a source 5G wireless communication system, and on a 5G-freshness parameter;
- forwarding the first 4G-master key to a target mobility managing entity (MME) of a target 4G wireless communication system for enabling deriving a second 4G-master key based on the first 4G-master key and a 4G-freshness parameter;
- and
- forwarding the 5G-freshness parameter to the user equipment for enabling deriving the first 4G-master key based on the 5G key, KAMF, and the 5G-freshness parameter and deriving the second 4G-master key based on the first 4G-master key and the 4G-freshness parameter.
A method performed by a host computer in a communication system, comprising:
- providing user data;
- and
- forwarding the user data to a cellular network, via a communication interface, for transmission to a user equipment (UE), wherein the cellular network comprises a key management arrangement configured to perform operations comprising:
- deriving a first 4G-master key based on a 5G key, KAMF, available at an Access and Mobility management Function (AMF) constituting a core network node supporting mobility management of a source 5G wireless communication system, and on a 5G-freshness parameter;
- forwarding the first 4G-master key to a target mobility managing entity (MME) of a target 4G wireless communication system for enabling deriving a second 4G-master key based on the first 4G-master key and a 4G-freshness parameter;
- and
- forwarding the 5G-freshness parameter to the user equipment for enabling deriving the first 4G-master key based on the 5G key, KAMF, and the 5G-freshness parameter and deriving the second 4G-master key based on the first 4G-master key and the 4G-freshness parameter.
Dependencies are inferred from the claim text.