API-Docs

This is the API-docs for Cherry relase o-du/l2.

Introduction

This document lists the APIs implemented between various modules of ODU-High and their functionality. These are in line with ORAN-WG8.AAD-v2.05.00, hereafter referred to as AAD Spec.

API Functions

  1. RLC-MAC Interface

    • AAD Spec : section 9.2.1

    1. RLC to MAC

      1. Data Transfer(DL) : Transfers DL data to MAC as per Section 9.2.1.1 of the AAD Spec

      2. Buffer Status Reporting(DL) : Reports DL data volume pending in the RLC entity, as per Section 9.2.1.4 of the AAD Spec

    2. MAC to RLC

      1. Data Transfer(UL) : Transfers UL data to RLC as per Section 9.2.1.2 of the AAD Spec

      2. Schedule Result Reporting (DL) : Reports DL schedule result to RLC as per Section 9.2.1.3 of the AAD Spec

  2. MAC-Scheduler Interface

    • AAD Spec : section 9.2.2

    1. MAC to Scheduler

      1. Air Interface Time : Sends timing information over air interface in terms of SFN and slo, as per Section 9.2.2.1.1 of the AAD Spec

      2. Cell Configuration Request : MAC provides SCH the cell configuration as per Section 9.2.2.2.1 of the AAD Spec

      3. Add UE Configuration Request : MAC provides SCH the configuration/capabilities of a UE as per Section 9.2.2.2.3 of the AAD Spec

      4. Modify UE Reconfiguration Request : MAC provides SCH the re-configuration of UE, also used to add/release/modify existing bearers, as per Section 9.2.2.2.4 of the AAD Spec

      5. RACH Indication : MAC receives the RACH Indication and share the contents with SCH as per Section 9.2.2.2.10 of the AAD Spec

      6. DL RLC Buffer Status Information : Reports data volume per LC when it is received at MAC as per Section 9.2.2.2.14 of the AAD Spec

      7. UL Buffer Status Report Indication : On reception and decoding of received BSR from the UE, MAC provides SCH buffer status report for UL scheduling, as per Section 9.2.2.2.16 of the AAD Spec

    2. Scheduler to MAC

      1. Cell Configuration Response - Response to cell configuration request from MAC, as per Section 9.2.2.3.1 of the AAD Spec

      2. UE Reconfiguration Response - Response to UE reconfiguration request from MAC, as per Section 9.2.2.3.3 of the AAD Spec

      3. DL Scheduling Information - Provides scheduling information for a given slot for downlink data, as per Section 9.2.2.3.5 of the AAD spec.

      4. UL Scheduling Information - Provides scheduled information for MAC to form the UL_TTI.request towards O-DU Low, as per Section 9.2.2.3.6 of the AAD Spec.

      5. RAR Information - Informs MAC of uplink scheduling and Msg3 scheduling information, as per Section 9.2.2.3.7 of the AAD Spec.

      6. Downlink Control Channel Information - Provides DCI scheduling information for a given slot on PDCCH, as per Section 9.2.2.3.8 of the AAD Spec

      7. Downlink Broadcast Allocation - Provides DCI and DL data scheduling information for SIB1 for a given slot for Broadcast Channel, as per Section 9.2.2.3.9 of the AAD Spec.

  3. DU APP - MAC Interface

    • AAD Spec : section 9.2.3

    1. DU APP to MAC

      1. Cell Start - Commands MAC to start cell at L1 and to start broadcasting system information, as per Section 9.2.3.1 of the AAD Spec.

      2. UE Create Request - Adds UE information at MAC as per Section 9.2.3.3 of the AAD Spec.

      3. UE Reconfiguration Request - Reconfigure UE information for a UE already added at MAC, as per Section 9.2.3.5 of the AAD Spec.

      4. DL CCCH Indication - Sends DL CCCH Message to MAC to be sent to UE, as per Section 9.2.3.16 of the AAD Spec.

    2. MAC to DU APP

      1. UE Create Response - Response to UE Create Request from DU Manager as per Section 9.2.3.4 of the AAD Spec.

      2. UE Reconfiguration Response - Response to UE Reconfiguration Request from DU APP as per Section 9.2.3.6 of the AAD Spec.

      3. UL-CCCH Indication - Sends the UL CCCH Message received from UE to DU APP as per Section 9.2.3.15 of AAD Spec.

  4. DU APP - RLC Interface

    • AAD Spec : section 9.2.4

    1. DU APP to RLC

      1. UE Create - Adds UE associated RLC entity and related information as per Section 9.2.4.1 of the AAD Spec.

      2. UE Reconfiguration - Reconfigures the UE associated RLC entity previously added at RLC, as per Section 9.2.4.1 of the AAD Spec.

      3. DL RRC Message Transfer - Requests RLC to deliver RRC message from CU to the UE, as per Section 9.2.4.3 of the AAD Spec.

    2. RLC to DU APP

      1. UL RRC Message Tranfer - Delivers RRC Message from UE to CU as per Section 9.2.4.4 of the AAD spec.

      2. RRC Message Delivery Report - Informs DU Manager on failed/successful delivery of a DL RRC message to UE, as per Section 9.2.4.5 of the AAD Spec.

Additional APIs

  1. DU APP - MAC Interface

    1. DU APP to MAC

      1. Cell Configuration Request - Configures cell information at MAC

    2. MAC to DU APP

      1. Cell Configuration Response - Response to Cell Configuration Request from DU APP

  2. DU APP - RLC Interface

    1. RLC to DU APP

      1. UE Create Response - Response to UE Create Request from DU APP

      2. UE Reconfiguration Response - Response to UE Recofiguration Request from DU APP

      3. DL RRC Message Response - Informs DU APP if a DL RRC Message was successfuly processed at RLC and sent to MAC.

  3. DU APP - O1 Interface

    1. DU sends alarms to O1 for cell up and cell down events using the alarm interface API