Create Communication System to Connect to SAP BTP, ABAP Environment.

Open SAP BTP cockpit and select your global account.

Select your global account.

Click Subaccounts.

Select your subaccount.

On your left menu select Destinations under Connectivity and click Download Trust.

Open SAP S/4HANA Cloud system as an administrator.

Go to Identity and Access Management and select the Maintain Business Roles tile.

Click New to create a new business role.

Define your business role and your business role ID and click Create.

Select Assigned Business Catalogs tab and click Add.

Search SAP_CORE_BC_COM, select it, apply the change and click OK.

Save your changes.

Go to Communication Management and select the Communication Arrangements tile.

Click New to add a new communication arrangement.

Select SAP_COM_0008 as scenario and give your arrangement a name.
SAP _COM_0008 as the communication scenario is needed to set up the communication with the business partner.

Click Create.

As a result you get following display. Click Create.

Click New to create a new communication system.

Enter system ID and name. Click Create.

Open SAP BTP cockpit, navigate to your subaccount. On the left menu select Instances and Subscriptions under Services. Click Instances, select your ABAP instance and click on it. Now scroll to Service Keys on the right side, select the menu and click View.

Copy the URL without the https:// for later use.

Switch to your SAP S/4HANA Cloud system, open your communication system, paste the URL as your host name. Enter DUMMY as logical system and business system. Don’ t click save yet.

Set OAuth 2.0 Identity Provider area ON. Upload the certificate you downloaded in step 1.5 from your SAP BTP cockpit. Copy the common name (the string after CN=) from the signing certificate subject or the signing certificate issuer and paste it into the OAuth 2.0 SAML Issuer field.

Don’t save yet.

Choose + in the inbound communication area to add a new communication user for inbound communication in SAP S/4HANA Cloud.

Choose New User.

Enter your communication system name as user name and description. Click Propose Password to generate a password and
Click Create.

Click OK.

Choose + in the outbound communication user area to create a outbound communication user.

Select SSL Client Certificate as authentication method and Client Default as client certificate. Click Create.

Choose Save to save your communication system.