+.. This work is licensed under a Creative Commons Attribution 4.0 International License.
+.. http://creativecommons.org/licenses/by/4.0
+
+
+
+API-Docs
+========
+
+This is the API-docs for Cherry relase o-du/l2.
+
+.. contents::
+ :depth: 3
+ :local:
+
+
+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
+
+ A. RLC to MAC
+
+ a. Data Transfer(DL) : Transfers DL data to MAC as per Section 9.2.1.1 of the AAD Spec
+
+ b. Buffer Status Reporting(DL) : Reports DL data volume pending in the RLC entity, as per Section 9.2.1.4 of the
+ AAD Spec
+
+ B. MAC to RLC
+
+ a. Data Transfer(UL) : Transfers UL data to RLC as per Section 9.2.1.2 of the AAD Spec
+ b. 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
+
+ A. MAC to Scheduler
+
+ a. 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
+
+ b. Cell Configuration Request : MAC provides SCH the cell configuration as per Section 9.2.2.2.1 of the AAD Spec
+
+ c. 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
+
+ d. 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
+
+ e. 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
+
+ f. 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
+
+ g. 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
+
+ B. Scheduler to MAC
+
+ a. Cell Configuration Response - Response to cell configuration request from MAC, as per Section 9.2.2.3.1 of the
+ AAD Spec
+
+ b. UE Reconfiguration Response - Response to UE reconfiguration request from MAC, as per Section 9.2.2.3.3 of the
+ AAD Spec
+
+ c. 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.
+
+ d. 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.
+
+ e. RAR Information - Informs MAC of uplink scheduling and Msg3 scheduling information, as per Section 9.2.2.3.7 of
+ the AAD Spec.
+
+ f. 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
+
+ g. 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
+
+ A. DU APP to MAC
+
+ a. 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.
+
+ b. UE Create Request - Adds UE information at MAC as per Section 9.2.3.3 of the AAD Spec.
+
+ c. UE Reconfiguration Request - Reconfigure UE information for a UE already added at MAC, as per Section 9.2.3.5
+ of the AAD Spec.
+
+ d. 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.
+
+ B. MAC to DU APP
+
+ a. UE Create Response - Response to UE Create Request from DU Manager as per Section 9.2.3.4 of the AAD Spec.
+
+ b. UE Reconfiguration Response - Response to UE Reconfiguration Request from DU APP as per Section 9.2.3.6 of the
+ AAD Spec.
+
+ c. 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
+
+ A. DU APP to RLC
+
+ a. UE Create - Adds UE associated RLC entity and related information as per Section 9.2.4.1 of the AAD Spec.
+
+ b. UE Reconfiguration - Reconfigures the UE associated RLC entity previously added at RLC, as per Section 9.2.4.1
+ of the AAD Spec.
+
+ c. 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.
+
+ B. RLC to DU APP
+
+ a. UL RRC Message Tranfer - Delivers RRC Message from UE to CU as per Section 9.2.4.4 of the AAD spec.
+
+ b. 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
+----------------
+
+These APIs are not defined in the AAD Spec but were implemented in O-DU High to achieve UE attach.
+
+1. DU APP - MAC Interface
+
+ A. DU APP to MAC
+
+ a. Cell Configuration Request - Configures cell information at MAC
+
+ B. MAC to DU APP
+
+ a. Cell Configuration Response - Response to Cell Configuration Request from DU APP
+
+2. DU APP - RLC Interface
+
+ A. RLC to DU APP
+
+ a. UE Create Response - Response to UE Create Request from DU APP
+
+ b. UE Reconfiguration Response - Response to UE Recofiguration Request from DU APP
+
+ c. DL RRC Message Response - Informs DU APP if a DL RRC Message was successfuly processed at RLC and sent to MAC.
+