Security solution for switching on and off security for up data between UE and RAN in 5G

1. A method comprising:

a user equipment (UE) transmitting, via a radio access network (RAN) node, a Protocol Data Unit (PDU) Session Establishment Request message toward a Session Management Function (SMF); and

after transmitting the PDU Session Establishment Request message, the UE receiving from the RAN node a Radio Resource Control (RRC) Connection Reconfiguration message comprising: i) a PDU session identifier (ID), ii) a PDU Session Establishment Accept message generated by the SMF, and iii) a user plane (UP) security policy for the PDU Session identified by the PDU session ID, wherein:

the UP security policy for the PDU session indicates:

i) whether UP confidentiality protection shall be activated or not for all data radio bearers (DRBs) belonging to the PDU session; and/or

ii) whether UP integrity protection shall be activated or not for all data radio bearers (DRBs) belonging to the PDU session.

2. The method of claim 1 , further comprising activating at least one of: confidentiality protection or integrity protection for the PDU Session.

3. The method of claim 1 , further comprising:

receiving a decision from a home network that security protection of UP data terminating in the RAN is not to be used by the UE, and

responsively precluding operational use by the UE of an algorithm to, at least one of, encrypt or integrity protect UP data sent on all radio bearers serving at least one of a Slice ID or a PDU Session ID between the UE and the RAN.

4. A method for operating a network node of a communication network that is configured to communicate with a user equipment (UE), the method comprising:

receiving a Protocol Data Unit (PDU) Session Establishment Request message for establishing a PDU session, wherein the PDU Session Establishment Request message was transmitted by the UE and includes a PDU session identifier (ID);

communicating a Session Management (SM) Request comprising the PDU Session Establishment Request to a Session Management Function (SMF) of the communication network; and

receiving from the SMF a message that includes: i) the PDU Session ID identifying the PDU session, ii) a PDU Session Establishment Accept message, and iii) a user plane (UP) security policy for the PDU session, wherein:

the UP security policy for the PDU session indicates:

i) whether UP confidentiality protection shall be activated or not for all data radio bearers (DRBs) belonging to the PDU session, and/or

ii) whether UP integrity protection shall be activated or not for all data radio bearers (DRBs) belonging to the PDU session.

5. The method of claim 4 , wherein the method is performed by an Access and Mobility Management Function, AMF, in the communication network.

6. The method of claim 5 , further comprising:

communicating to the SMF, policy information that identifies whether the SMF is allowed to request a change to RAN security.

7. The method of claim 5 , further comprising:

communicating to the SMF, a default security policy value indicating at least one of: whether the UE uses encryption protection for UP data terminating in the RAN by default; and whether the UE uses integrity protection for UP data terminating in the RAN by default.

8. The method of claim 5 , further comprising transmitting to a RAN node a PDU session request comprising: i) the PDU Session ID identifying the PDU session, ii) the PDU Session Establishment Accept message, and iii) the UP security policy for the PDU session.

9. A method for operating a base station of a communication network that is configured to communicate with a user equipment (UE), the method comprising:

the base station receiving from a UE a message comprising a Protocol Data Unit (PDU) Session Establishment Request message, the PDU Session Establishment Request message comprising a PDU session identifier (ID);

the base station forwarding the PDU Session Establishment Request message to an Access and Management Function (AMF);

the base station receiving from the AMF a PDU session request comprising: i) the PDU Session ID, ii) a PDU Session Establishment Accept message generated by a Session Management Function (SMF), and iii) a user plane (UP) security policy for the PDU session identified by the PDU session ID; and

the base station transmitting to the UE a Radio Resource Control (RRC) Connection Reconfiguration message comprising the PDU Session Establishment Accept message generated by the SMF, wherein

the UP security policy for the PDU session indicates:

i) whether UP confidentiality protection shall be activated or not for all data radio bearers (DRBs) belonging to the PDU session, and/or

ii) whether UP integrity protection shall be activated or not for all data radio bearers (DRBs) belonging to the PDU session.

10. The method of claim 9 , wherein the method is performed by a network node in the RAN.

11. The method of claim 9 , further comprising including selected algorithms for at least one of integrity protection or encryption in the RRC Connection Reconfiguration message.

12. A method for operating a Session Management Function (SMF) of a communication network that is configured to communicate with an Access and Mobility Management Function (AMF) of the communication network, the method comprising:

the SMF receiving from the AMF a Session Management (SM) Request comprising a PDU Session Establishment Request for a user equipment (UE); and

the SMF communicating to the AMF a message that includes: i) a PDU Session ID identifying a PDU session, ii) a PDU Session Establishment Accept message, and iii) a user plane (UP) security policy for the PDU session, wherein

the UP security for the PDU session indicates:

i) whether UP confidentiality protection shall be activated or not for all data radio bearers (DRBs) belonging to the PDU session, and/or

ii) whether UP integrity protection shall be activated or not for all data radio bearers (DRBs) belonging to the PDU session.

13. The method of claim 12 , further comprising:

receiving with the SM request, policy information that identifies whether the SMF is allowed to request a change to RAN security.

14. The method of claim 12 , further comprising:

responsive the receiving, determining whether the SMF contains a common local policy that applies to all UEs and, if not, communicating a subscription data request to a Unified Data Management, UDM, to retrieve SM-related subscription data for the UE related with a Data Network Name, DNN.

15. The method of claim 14 , wherein:

the retrieved SM-related subscription data for the UE identifies whether to operate using security protection that comprises at least one of:

encryption protection for UP data terminating in the RAN; and

integrity protection for UP data terminating in the RAN.

16. The method of claim 12 , wherein the SM Request Ack message includes at least one of: a SMF request of security protection of UP data terminated in the RAN, a SMF decision of Core Network (CN) terminated security protection of UP data in a serving network, or a home network decision of CN terminated security protection of UP data in the home network.

17. The method of claim 12 , further comprising:

responsive the receiving, obtaining a policy for security protection of UP data terminating in a RAN from a Policy Control Function.

18. A user equipment (UE) that wirelessly communicates with a communication network, the UE comprising: a transmitter; and

a receiver, wherein the UE is configured to:

use the transmitter to transmit, via a radio access network (RAN) node, a Protocol Data Unit (PDU) Session Establishment Request message toward a Session Management Function (SMF) in a communication network; and

after transmitting the PDU Session Establishment Request message, use the receiver to receive from the RAN node a Radio Resource Control (RRC) Connection Reconfiguration message comprising: i) a PDU session identifier (ID), ii) a PDU Session Establishment Accept message generated by the SMF, and iii) a user plane (UP) security policy for the PDU Session identified by the PDU session ID, wherein

the UP security policy for the PDU session indicates:

i) whether UP confidentiality protection shall be activated or not for all data radio bearers (DRBs) belonging to the PDU session, and/or

ii) whether UP integrity protection shall be activated or not for all data radio bearers (DRBs) belonging to the PDU session.