ONAP/3GPP & ORAN Alignment: A1 Adapter extensions

Use Case Name

A1 Adapter Extensions

@Michela Bevilacqua , @John Keeney (Ericsson EST)

Use Case Key Information

Topic

Description

Link

Topic

Description

Link

Wiki Page

Documentation

O-RAN A1 Policies in ONAP (Non-RealTime RIC)

Architecture Subcommittee

Presentations and JIRA Tickets for Architecture Subcommittee made May 26, 2020 

https://lf-onap.atlassian.net/browse/ONAPARC-580

5G Use Case Requirement

JIRA Ticket for Guilin Use Case Requirements

REQ-352: Extend ORAN A1 Adapter and add A1 Policy Management - GuilinDone

CCSDK Requirement/Epic

JIRA Ticket for Epic for A1 Adapter Evolution in Guilin

https://lf-onap.atlassian.net/browse/CCSDK-2475

CCSDK Requirement/Epic

JIRA Ticket for Epic for A1 Policy Management in Guilin

https://lf-onap.atlassian.net/browse/CCSDK-2476

Integration Story

JIRA Ticket for User Story for Integration testing with OSC A1 simulator 

 https://lf-onap.atlassian.net/browse/INT-1654

CSIT Story

Add CSIT tests to show A1 Policy end-to-end flow - Guilin

https://lf-onap.atlassian.net/browse/CCSDK-2700

CCSDK A1 Policy Management Service NBI / API

JIRA Ticket for CCSDK A1 Policy Management Service NBI/API - Guilin

https://lf-onap.atlassian.net/browse/CCSDK-2489
See also: Open API (yaml)

Deployment (A1 Adapter)

Story for deploying A1 adapter in Guilin (SDNC, CCSDK, OOM)

https://lf-onap.atlassian.net/browse/CCSDK-2493

Deployment (A1 Policy Management)

Story for A1 Policy Management in Guilin (OOM)

https://lf-onap.atlassian.net/browse/CCSDK-2492

Testing

Story for TEST Release Requirement (+ linked resources)

https://lf-onap.atlassian.net/browse/REQ-447

API Documentation

Stories for Documentation (A1 Policy Management Service & A1 Adapter)

https://lf-onap.atlassian.net/browse/CCSDK-2832

https://lf-onap.atlassian.net/browse/CCSDK-2833





Business Driver

EXECUTIVE SUMMARY This requirement enhances the A1 adapter/interface capabilities provided in Rel 6 as part of  5G/ORAN & 3GPP Standards Harmonization requirement ( REQ-38).   O-RAN has defined A1 interface specification in the context of the management of 5G RAN elements to provide intent based policies for optimization of the RAN network performance. Planned enhancements for Rel 7 include additional support for managing A1 Policies, multiple A1 targets in the RAN, multi-version support for different A1 targets, and secure TLS communication.

BUSINESS IMPACT- Continuing the convergency between ONAP and ORAN initiated in Rel 6, A1 interface can be used by all service providers and avoid duplicate development effort.

.BUSINESS MARKETS -Enhanced A1 capabilities, once developed, will be useable by any service provider deploying and using ONAP.

FUNDING/FINANCIAL IMPACTS - A1 interface provides a flexible way for the operator to manage wide area RAN network optimization, reducing capex investment needs.

ORGANIZATION MGMT, SALES STRATEGIES - There is no additional organizational management or sales strategies for this use case outside of a service providers "normal" ONAP deployment and its attendant organizational resources from a service provider.

Development Status



PROJECT

PTL

User Story / Epic

Requirement

A&AI

@James Forsyth

NO IMPACT



AAF

@Jonathan Gathman

NO IMPACT



APPC

@Takamune Cho

NO IMPACT



CLAMP

@Gervais-Martial Ngueko

TBC



CC-SDK

@Dan Timoney

  • Extend existing A1 Adapter functionality in CCSDK

  • Add additional support for A1 Policy Management

https://lf-onap.atlassian.net/browse/CCSDK-2475

https://lf-onap.atlassian.net/browse/CCSDK-2476

DCAE

@Vijay Kumar

NO IMPACT



DMaaP

@Mandar Sawant

NO IMPACT



External API

@Matthieu Geerebaert

NO IMPACT



MODELING

@Hui Deng

TBC



Multi-VIM / Cloud

@Bin Yang

NO IMPACT



OOF

@Shankaranarayanan Puzhavakath Narayanan

TBC



POLICY

@Pamela Dragosh

NO IMPACT



PORTAL

@Manoop Talasila

NO IMPACT



SDN-C

@Dan Timoney

  • Extend existing A1 Adapter functionality in SDNC / SDNR



SDC

@Ofir Sonsino

NO IMPACT



SO

@Seshu Kumar Mudiganti

NO IMPACT



VID

@ittay

NO IMPACT



VNFRQTS

@Steven wright

NO IMPACT



VNF-SDK

@victor gao

NO IMPACT



CDS

@Yuriy Malakov

NO IMPACT



Owners

@John Keeney (Ericsson EST)

@Michela Bevilacqua

Background

O-RAN A1 Interface:

  • The O-RAN architecture introduces a new management interface - “A1 interface” - between the network management system and the radio access network (RAN)

    • A1-AP (Application Protocol) specified by O-RAN Alliance WG2

  • A1 interface enables vendor-agnostic policy-based guidance (“A1 Policies”) to be sent to underlying RAN elements from the management system.

    • “A1-EI” will also support transmission of enrichment information from the management platform to the RAN elements (Still being defined – currently out of scope)

    • “A1-ML/AI” may also assist with ML Model management in the RAN (Still being defined – currently out of scope)

  • The A1 interface connects Non-RealTime-RIC logical function in OAM/SMO layer with the Near-RealTime-RIC logical function in the RAN.

A1 in O-RAN Architecture for Disaggregated RAN

A1 in O-RAN Architecture
A1 in O-RAN Architecture

A1 Adapter in Frankfurt

  • Implemented as an SDNC/CCSDK extension to terminate & expose A1 interface

  • https://lf-onap.atlassian.net/wiki/display/DW/A1+Adapter+in+ONAP

  • Developed for Release Requirement (REQ-38): 5G / ORAN & 3GPP Standards Harmonization

  • Can be used by other ONAP functions to perform A1 Policy Operations over A1 Interface

  • Provides DMaaP northbound interface, and REST (A1) southbound interface

Enhancements for Guilin Release

  • Add additional support for standardized A1 protocol (O-RAN A1-AP v1.1)

    • Current (Frankfurt) supports only O-RAN-SC’s (draft) non-spec version of A1 Application Protocol

    • Will add support for upcoming A1 standard spec evolution

    • Will add support for multiple versions for different A1 connections

  • Managing A1 Policies

    • Operations:

      • Query A1 Policy Types in near-RT-RICs

      • Create/Query/Update/Delete A1 Policy Instances in near-RT-RICs

      • Query Status for A1 Policy Instances

    • Maintain transient cache of RAN’s A1 Policy information

      • Support RAN-wide view of A1 Policy information

      • Streamline A1 traffic

      • Enable (optional) re-synchronization after inconsistencies / near-RT-RIC restarts

  • Add support for multiple near-RT-RICs (with multi-version support)

  • Unified REST & DMaaP NBI

  • Add support for TLS/HTTPS REST for southbound A1 interfaces (and NBIs)

    • Leverage existing ONAP cert management approaches

  • Converge ONAP & O-RAN-SC A1 Adapter/Controller functions in ONAP SDNC/CCSDK

    • Proposed functionality is currently available as 2 functions in O-RAN-SC

    • Basic A1 Adapter is an ODL extension & Policy Management is a separate microservice

A1 Policies - Northbound Interface (REST & DMaaP) Proposed

  • See