SAP Customer Activity Repository will typically have a two way communication with ECC when it comes to integration.
A)Inbound integration into SAP CAR from SAP ECC(using SLT )
Below are few options through which the integration can occur
1)SLT is a separate standalone system server that replicates data from SAP ECC into SAP CAR
2)SLT is installed within SAP ECC and integrates with SAP CAR(for data replication)
As part of SAP CARAB 4.0, more than 200 tables in both S4 HANA and SAP ECC can be replicated into SAP CAR
SLT is System Landscape Replication Server that replicates the below data from SAP ECC into SAP CAR for master data checks,cost price/gross margin calculation,inventory visibility and various other analytics/reports
1.Master data such as Article/Site/Promotions etc
2.Inventory data such as Stock quantities for a particular article/store combination and also stock in transit details etc
3.Sales documents – Details such as sales orders and also billing documents
B)Inbound Integration into SAP CAR from SAP ECC(for DDF using DRFOUT)
If Demand Data Foundation is enabled as a business function, then master data from SAP ECC is required to be transferred into SAP CAR for demand modelling, forecasting etc. This is achieved using DRFOUT framework(RFC connection) from SAP ECC primarily for the below information
7)Source of Supply
8)Distribution Chain(Sales Org, Distribution channel)
Unified Demand Forecast is another module within SAP CAR that utilises DDF master data that feeds into UDF algorithm engine for accurate forecasting(SAP suggests to have 2 years of historical sales data as well for accurate forecasting numbers)
Outbound Integration with SAP ECC
Outbound Integration from SAP CAR into SAP ECC(using Idocs)
This integration typically consists of the below idocs
1.WPUUMS – Aggregated Sales data (that posts both Billing and Article documents in SAP ECC)
2.WPUBON – Sales per receipt(that posts both Billing and Article documents in SAP ECC)
3.WPUTAB – Payment information such as cash,credit,debit,cheque, gift card etc.
4.WPUFIB – Financial Transactions such as Paid in, Paid out etc
5.WPUWBW – Goods Movements data that may also include scraps, write offs, damaged items etc depending on the business processes/requirements.
Inventory visibility is one of the key features of SAP CAR and it requires the idoc confirmation settings to be turned on in POSDTA configuration for the respective tasks that sends the request to SAP ECC and receives the confirmation back into SAP CAR, which then updates the unprocessed sales record count in /POSDW/TLOGUS table in POSDTA.
You can also refer to my other blogs on SAP CAR using the below URLs
POSDM Vs POSDTA
Journey from POSDM to POSDTA(CAR)
Migration from POSDM to POSDTA(CAR)
SAP CAR integration with S/4 HANA