Important Note: SAP Ariba consists of multiple solutions, so this series has been divided into several parts to ensure clear and easy understanding. You can refer to the other parts of this series through the blog links provided at the end of this post.

What is Upstream and Downstream in SAP Ariba ?

In this blog, I am going to explain in detail What Are the Different SAP Ariba Solutions Architecture. Before diving into the topic, we need to understand that SAP Ariba solutions are divided into two parts: Upstream and Downstream.

Let’s first understand what Upstream and Downstream mean.

⦁ Upstream
Upstream processes focus on sourcing and supplier management activities. In the upstream phase, organizations identify and onboard suppliers through Ariba Supplier Lifecycle and Performance (SLP) or Supplier Registration. Once suppliers are registered or qualified, buyers can conduct sourcing events such as RFIs, RFQs, auctions, and negotiate the best possible deals.
Upstream also includes contract creation and management, where organizations draft, negotiate, and sign contracts with suppliers.
⦁ Downstream
Downstream processes cover the operational, procurement, and transactional activities. While upstream focuses on finding and selecting suppliers, downstream handles the full Procure-to-Pay (P2P) cycle, where actual day-to-day purchasing and payment operations occur. This includes requisitions, purchase orders, goods receipts, invoicing, and payments.

Note – Ariba has multiple solutions, but in this blog I have mentioned only the solutions that are popular and widely used across organizations.

Supplier Lifecycle Management (SLP):

The Ariba Supplier Lifecycle Management (SLP) architecture flow is divided into two parts: SAP S/4HANA to Ariba and Ariba to SAP S/4HANA.

Now, a question may come to your mind—why does Ariba SLP have two process flows?

The answer is simple:
⦁ The first process is used only for registering existing suppliers (legacy suppliers) that already exist in S/4HANA and need to be replicated to Ariba SLP.
⦁ The second process is used when a supplier is new. In this case, the supplier must go through the qualification stages, and once they complete the process successfully, they become registered in Ariba SLP.

i) SAP S/4HANA to Ariba

This first flow is used to send suppliers to Ariba SLP who already exist in S/4HANA to Ariba SLP.

a. The suppliers that are already present in S/4HANA are often called legacy suppliers. We execute the DRFOUT transaction, and the supplier data is sent through a webservice, which first reaches CIG. On CIG, the Business Partner Suite Replicate Request Out Webservice is generated, and then all supplier data is successfully delivered to Ariba SLP.

b. Once the supplier data reaches Ariba SLP, Ariba sends a confirmation back to S/4HANA indicating that the supplier data was successfully received in Ariba SLP. From Ariba, the Business Partner Suite Replicate Confirmation In Webservice is generated in CIG, and then CIG sends the response to S/4HANA through the Cloud Connector (CC).

ii) Ariba to SAP S/4HANA

This is the 2nd process flow of Ariba SLP. This is use for new suppliers.

a. The starting point of this flow is Ariba. First, the supplier fills out the Supplier Request form, which will then go through an Approve/Reject process. After approval, the supplier enters the Pre-qualification stage, where they must complete a set of Qualification criteria defined by the buyer. Once this step is completed, the Qualification Approval/Rejection takes place. After receiving final approval, the supplier is officially Registered in Ariba SLP.

b. Now the supplier is officially registered in Ariba SLP, but organizations generally send their Ariba supplier data to S/4HANA. (This approach is commonly followed by almost every entity.) In the diagram above, you can see the Manual Sync option, which means that when a supplier is registered in Ariba SLP, we manually trigger the sync to send the new supplier data to S/4HANA.

Note: We can also configure the system for Auto Sync.

c. When we trigger the sync, the supplier data is sent through the Webservice to CIG, where the Business Partner Suite Replicate Request In service is generated. From CIG, the data then reaches S/4HANA via the Cloud Connector (CC).

d. Now the supplier data has successfully reached S/4HANA, but Ariba also needs confirmation. Therefore, the Business Partner Suite Replicate Confirmation Out Webservice is triggered from S/4HANA to CIG, and CIG then sends the confirmation back to Ariba.

Why is there no qualification process in the first Ariba SLP flow?
The answer is very simple — in the first process, we are sending suppliers to Ariba SLP who already exist in the ERP system and have been associated with the entity for a long time. These are legacy suppliers, and the organization already knows their background and has been doing business with them for years. Therefore, qualification criteria are not required for them.

Important points to keep in mind

⦁ In the Ariba SLP solution, all message types are handled through Webservices; no IDocs are used.

⦁ CIG stands for Cloud Integration Gateway. It is a central platform that handles all integration activities. CIG is the older
name — the current name is Managed Gateway for Spend Management and Business Network. In this blog, we continue to use the name CIG because many people still commonly refer to it as CIG.

⦁ S/4HANA uses XML, while Ariba uses cXML. Therefore, whenever data is exchanged from S/4HANA to Ariba, CIG converts XML into cXML. Similarly, when data flows from Ariba to S/4HANA, CIG converts cXML back into XML.

⦁ Cloud Connector (CC) acts as a firewall and secure tunnel between CIG and S/4HANA. Whenever data flows from CIG to S/4HANA, it always passes through the Cloud Connector.

Note: CC is only involved when the data flow direction is from CIG to S/4HANA.