1. Cloud Native Core Policy User's Guide
  2. About Cloud Native Core Policy Services

3 About Cloud Native Core Policy Services

About Session Management Service

Oracle Communications Policy Control Function (PCF) implements policy control for session management for service data flows. PCF implements N7 interface to trigger session management policies towards Session Management Function (SMF). SMF controls the User plane Function (UPF) . It translates policies received from the PCF to a set of directives/information understood to the UPF and then forwards it to the UPF.

Session Management Service supports the following:

  • Enforcement control of policy decisions related to QoS, charging, gating, service flow detection, packet routing and forwarding, traffic usage reporting.
  • Enforcement of QoS, charging, gating, service flow detection, packet routing and forwarding and traffic accounting and reporting policy decisions can be distributed among the UPF, Radio Access Network (RAN) and User Equipment (UE) depending on the policy type.

Oracle Communications PCF supports the following 3GPP defined services for Session Management:

Table 3-1 Session Management Services

Service Operation Name Description Initiated By Resource URI HTTP Method
Npcf_SMPolicyControl_Create Request to create an SM Policy Association with the PCF to receive the policy for a PDU session SMF {apiRoot}/npcf-smpolicycontrol/v1/sm-policies POST
Npcf_SMPolicyControl_Delete Request to delete the SM Policy Association and the associated resources SMF {apiRoot}/npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}/delete POST
Npcf_SMPolicyControl_Update Request to update the SM Policy association with the PCF to receive the updated policy when Policy Control Request Trigger condition is met SMF {apiRoot}/npcf-smpolicycontrol/v1/sm-policies/{smPolicyId}/update POST
Npcf_SMPolicyControl_UpdateNotify Update and/or delete the PCC rule(s) PDU session related policy context at the SMF and Policy Control Request Trigger information PCF

{Notification URI}/update

{Notification URI}/terminate

POST

About Access and Mobility Management Service

Oracle PCF implements access management service-related policies over N15 interface towards the Access and Mobility Management Function (AMF).

Access and Mobility Management Service supports the following:

  • Enforcement control of policy decisions related to Radio Access Technology (RAT)/Frequency Selection Priority
  • Enforcement of Service Area Restrictions is executed in the UE
  • Enable location tracking for a UE to get periodic updates on subscriber current location

Oracle Communications PCF supports the following 3GPP defined services for Access and Mobility Management:

Table 3-2 Access and Mobility Management Services

Service Operation Name Description Initiated By Resource URI HTTP Method
Npcf_AMPolicyControl_Create Creates an AM Policy Association and provides corresponding policies to the Network Function (NF) consumer AMF {apiRoot}/npcf-am-policy-control/v1/policies/ POST
Npcf_AMPolicyControl_Update Updates of an AM Policy Association and provides corresponding policies to the NF consumer when the policy control request trigger is met or the AMF is relocated due to the UE mobility and the old PCF is selected AMF {apiRoot}/npcf-am-policy-control/v1/policies/{polAssoId}/update POST
Npcf_AMPolicyControl_UpdateNotify Provides updated policies to the NF consumer PCF {{Notification URI}/update

{Notification URI}/terminate

POST
Npcf_AMPolicyControl_Delete Provides means for the NF consumer to delete the AM Policy Association AMF {apiRoot}/npcf-am-policy-control/v1/policies/{polAssoId} DELETE

About Policy Authorization Service

Oracle Communications Policy Control Function (PCF) implements policy authorization service that authorizes an Application Function (AF) request over N5 interface.

Policy Authorization Service supports the following:

  • Creates policies as requested by AF for the Protocol Data Unit (PDU) session. Policy authorization service is a critical function for IP Multimedia Subsystem (IMS) integration and dynamic Policy and Charging Control (PCC) rule creation

Oracle Communications PCF supports the following 3GPP defined services for Policy Authorization:

Table 3-3 Policy Authorization Services

Service Operation Name Description Initiated By Resource URI HTTP Method
Npcf_PolicyAuthorization_Create Determines and installs the policy according to the service information provided by an authorized NF service consumer. AF, Network Exposure Function (NEF) {apiRoot}/npcf-policyauthorization/v1/app-sessions POST
Npcf_PolicyAuthorization_Update Determines and updates the policy according to the modified service information provided by an authorized NF service consumer. AF, NEF {apiRoot}/npcf-policyauthorization/v1/app-sessions/{appSessionId} PATCH
Npcf_PolicyAuthorization_Delete Provides means to delete the application session context of the NF service consumer. AF, NEF {apiRoot}/npcf-policyauthorization/v1/app-sessions/{appSessionId}/delete POST
Npcf_PolicyAuthorization_Notify Notifies NF service consumer of the subscribed events. PCF

{notifUri}/notify

{notifUri}/terminate

POST
Npcf_PolicyAuthorization_Subscribe Allows NF service consumers to subscribe to the notification of events. AF, NEF {apiRoot}/npcf-policyauthorization/v1/app-sessions/{appSessionId}/events-subscription PUT
Npcf_PolicyAuthorization_Unsubscribe Allows NF service consumers to unsubscribe to the notification of events. AF, NEF {apiRoot}/npcf-policyauthorization/v1/app-sessions/{appSessionId}/events-subscription DELETE

About UE Management Service

Oracle PCF implements User Equipment (UE) management service-related policies over N15 interface towards the AMF.

UE Management Service supports the following:

  • Transfer of UE Route Selection Policies (URSP) rules to UE
  • Establish the UE Policy Association requested by the NF service consumer
  • Define and deliver URSP message to UE via AMF using N1N2 message

Oracle Communications PCF supports the following 3GPP defined services for UE Management:

Table 3-4 UE Management Services

Service Operation Name Description Initiated By Resource URI HTTP Method
Npcf_UEPolicyControl_Create Creates a UE Policy Association AMF {apiRoot}/npcf-ue-policy-control/v1/policies/ POST
Npcf_UEPolicyControl_Delete Provides means for the NF consumer to delete the UE Policy Association AMF {apiRoot}/npcf-ue-policy-control/v1/policies/{polAssoId} DELETE
N1N2MessageSubscribe Creates a subscription for N1 Message Transfer AMF {apiRoot}/namf-comm/<apiVersion>/ue-contexts/{ueContextId}/n1-n2-messages/subscriptions POST
N1N2MessageUnSubscribe Deletes a previously created subscription for N1 Message Transfer AMF {apiRoot}/namf-comm/<apiVersion>/ue-contexts/{ueContextId}/n1-n2-messages/subscriptions/{subscriptionId} DELETE
N1N2MessageTransfer Transfer an N1 message (NAS message) that is to be delivered to the UE AMF {apiRoot}/namf-comm/<apiVersion>/ue-contexts/{ueContextId}/n1-n2-messages POST
N1MessageNotify Indicate status of an N1 Message Transfer PCF {Notification URI} POST

About PCRF Core Service

Policy solution supports the Gx reference point for provisioning and removal of PCC rules from the PCRF to the PCEF and the transmission of traffic plane events from the PCEF to the PCRF.

PCRF Core Service supports the following:
  • IP-CAN session Establishment, Modification and Termination Support
  • Install/Modify/Remove Predefined PCC rules
  • Install/Modify/Remove Dynamic PCC rules
  • Gate function
  • Charging-related Information Support
  • Integration with AF (over Rx)
  • Presence Area Reporting Support
  • Time of the day procedures
  • Sponsored Data Connectivity Support
  • NSA related enhancements for QoS

About Binding Service

Binding service stores binding information related to 4G/5G subscribers and aid Diameter Gateway in forwarding Application Function (AF) requests. It also queries Network Repository Function (NRF) client for fetching Binding Support Function (BSF) information (One time Query and subscribe for notifications). For BSF, autonomous NRF discovery and static configuration is only supported , on-demand is not yet supported. Session Management service and PCRF- Core service send all the relevant information to Binding service asynchronously.

In CNC Policy, Diameter Gateway should have a converged mode, where
  • Diameter Gateway connects to PCRF-Core
  • Diameter Gateway also accepts a connection from Diameter Connector
In Converged mode of Diameter Gateway,
  • All Diameter Applications except Rx are routed to PCRF-Core.
  • For Rx messages, Diameter Gateway queries (asynchronously) Binding Service and based on the response will forward either to PCRF-Core or SM Service (via. Diameter Connector)

Configuration

In Helm Charts you need to configure diamgateway.envGatewayMode as converged in custom-values.yaml file, and the child helm files for Diameter-Gateway, Query-Service etc need to refer to this environment variable. This is mainly for performance considerations so that Diameter-Gateway and Query Service need not to query Binding service for the binding information. For more information on diamgateway.envGatewayMode, see Oracle Communications Cloud Native Core Policy Installation Guide.

Depending on the value of the following parameters, binding service or BSF is queried:
  • bindingEnable in custom-values.yaml file
  • Binding Operation in CNC Console GUI
Behaviour is as follows:
  • When both the configuration variables are set to true, binding service is queried.
  • When the bindingEnable parameter is set to true and the Binding Operation is configured to false, BSF is queried.
  • When the bindingEnable parameter is set to false and the Binding Operation is configured to true, neither BSF nor binding service is queried.
  • When both the configuration variables are set to false, neither BSF nor binding service is queried.

Binding Service Truth table when receiving AAR-I Following truth table will be considered by Binding Service for finding the context owner of a session.

Priority : Priority indicates that attributes if specified in the message will be considered as per the following priority from high to low. For example, IPv6 has higher priority indicates that if IPv6 is present then only IPv6 binding will be considered and corresponding context-owner information will be returned otherwise next attribute priority will be considered.
  • IPv6
  • IPv4 + APN/DNN+SNSSAI
  • IPv4
  • IMSI
  • MSISDN

Table 3-5 Binding Service Truth table when receiving AAR-I

S.No. Message IPv6 IPv4 APN/DNN+SNSSAI IP Domain ID GPSI/MSISDN SUPI/IMSI Binding Lookup Query
1 Gx-CCR I/SM Association P (Present in Gx CCR-I/N7 Sm create message) P P P P P IPv6
AAR - I P (Present in Rx AAR-I message) P P P    
2 Gx-CCRI/SM Association P P P P P P IPv4 + APN/(DNN+SNSSAI) + IP Domain ID
AAR - I   P P P    
3 Gx-CCRI/SM Association P P P P P P IPv4 (DNN and IP Domain ID won't be considered)
AAR - I   P     P P
4 Gx-CCRI/SM Association P P P   P P IPv4 + APN/(DNN+SNSSAI) + IP Domain IDIF No Records found (Would consider IP Domain ID as BLANK in Gx Session) => Not in the scope of PI-C (Need to enhance DB API for the same)
AAR - I   P P P    
Binding Service Truth table when receiving AAR-U

Table 3-6 Binding Service Truth table when receiving AAR-U

S.No. Message IPv6/IPv4 APN/DNN+SNSAAI Session ID Binding Lookup Query
1 AAR-U P P P Session-ID
2 AAR-U P P P IP Address + APN/DNN+SNSSAI (If Rx Session Id not Found in Binding DB)
3 AAR-U P   P IP Address (If Rx Session Id not Found in Binding DB)

Note:

  1. IP-CAN-Session Not available, when there is no suitable binding found in the binding service
  2. UNABLE-TO-COMPLY, when request times out at Diameter Gateway