set-up-inbound-rfc-from-on-premise-systems-using-websocket-rfc-b76751c.md

Set Up Inbound RFC from On-Premise Systems Using WebSocket RFC

Context

Use WebSocket RFC to establish an RFC connection from an on-premise system to the ABAP environment. WebSocket RFC makes it possible to call RFC function modules of the ABAP environment using the API URL of the cloud system using TLS-encrypted WebSocket connections.

Note:

All WebSocket-RFC-connections are TLS-encrypted. WebSocket RFC always uses HTTPS.

Procedure

1. Create a Communication Scenario that defines all RFMs to be called on the server side (inbound scenario). See Communication Scenario for more information.
2. Create a Communication Arrangement with a Communication System and a Communication User. See the following for more information:
   • Communication Arrangement
   • Communication System
   • Communication User

Settings in the On-Premise System

In the on-premise system, the following parameters must be set in transaction SM59.

Create a destination of connection type W:

Technical Settings
Host	The API-URL defined in the Communication Arrangement without the https:// prefix
Port	443
Logon & Security
Explicit Client	by Hostname
Authentication Method	by User/Password Note: If you choose user/password authentication, activate Alias User.
	by X.509 Certificate

Note:

These settings are available with SAP S/4HANA Cloud 1909. For older releases, you need to transform from a CPIC-based RFC to WebSocket RFC via Business Connector. See SAP Business Connector for more information.

Related Information

Develop a Remote-Enabled Function Module (RFM)