1. Background

The O-RAN architecture includes a Real-Time (RT) Radio Intelligent Controller (RIC) that is connected via A1 interface to Non-Real Time RIC function that resides in the Service Management and Orchestration (SMO) layer. The purpose of A1 interface is to enable Non-RT RIC function to provide policy-based guidance, AI/ML model management, and enrichment information to the near-RT RIC for RAN optimization.

2. High-Level Architecture and Use Cases

The overall Use Case Flow (DMAAP <--> SDNR/A1 REST Adapter <--> A1 Mediator) is as follows:

1. Any ONAP or micro-service that wants to perform any policy management related activity will publish a DMAAP message, with appropriate request
2. DMAAP listener will consume the DMAAP message and invoke RPC against A1 Adapter
3. A1 Adapter, based on the received DMAAP message/RPC, will invoke corresponding REST API's against A1 Mediator in Near-RT RIC

The picture below depicts overall use case flow

3. High-Level Design Approach

4. North-bound RPC YANG Model

5. DMAAP Message Format

6. A1 Mediator References

7. Deployment Considerations

8. Supporting Documents

A1-Adapter-ONAP-Ver6.pptx