Describing Scenarios for HTTP-based Communication with ABAP based SAP Systems

SAP delivered the first version of the SAP Internet Transaction Server (SAP ITS) with SAP R/3 3.1G in 1996. SAP ITS is a software that acts as a gateway between a Web server and an SAP system. It switches between general Internet protocols and formats (such as HTTP, HTTPS, and HTML) and those that are specific to the SAP system (such as DIAG, RFC, and dynpros (screens)).

First, the SAP ITS was implemented as standalone software, that was used "in front of" an ABAP-based SAP system (see the following figure). This "standalone" ITS existed as of Release 3.1G up to and including 6.20 (upwardly and downwardly compatible with SAP systems up to and including AS ABAP 6.40). As of AS ABAP 6.40, the new ITS is integrated in AS ABAP on all platforms with a simplified architecture.

Web applications that were developed specifically for SAP ITS are called Internet Application Components (IACs). These include Employee Self Services (ESS) that are based on SAP R/3 and SAP R/3 Enterprise or the SAP Online Store. The SAP GUI for HTML also uses the SAP ITS.

SAP ITS functionality (either standalone or integrated) is therefore required for existing Web applications (in IAC technology) and the SAP GUI for HTML, regardless of the AS ABAP release of the corresponding SAP system.

Based on the highly-scalable infrastructure, as of SAP Web AS 6.10 new technologies are used to process HTTP requests (and other protocols) directly from the internet or to send HTTP client requests to the internet. To achieve this, the SAP Kernel has been extended with the Internet Communication Manager (ICM) process.

The ICM process forwards requests to the Internet Communication Framework (ICF), which supports numerous programming models. This is how the SAP CRM, SAP BW, and SAP PI software components use this infrastructure. A programming model for such applications (among others) are the Business Server Pages (BSPs).

Web Dynpro is the preferred programming model for stateful desktop application Web interfaces in SAP Business Suite systems. It provides a clear distinction between the user interface (UI) and the business logic. It also provides functions that are not usually available as part of the standard tools for developing professional user interfaces. These include functions for checking entries, providing input help, supporting multiple languages, and handling errors comfortably, as well as caching mechanisms that ensure fast response times and are therefore especially useful for interactive user interfaces.

The Web Dynpro ABAP programming model is available as of AS ABAP 7.00.

SAPUI5 is the SAP implementation of the open HTML5 standard. The ICF can process Web pages based on HTML5 (for this, the plug-in UI_INFRA or the software component SAP_UI needs to be installed on the SAP system).

OData is an open standard that can be used by any software or device that communicates using the HTTP(S) protocol. It can parse and construct an XML document. OData can also be described as ODBC for the Web. SAP Gateway is the implementation of the OData standard on an AS ABAP-based SAP system (available for AS ABAP 7.00 onwards).

SAP Fiori is a collection of apps, which are created based on the rules of the SAP User Experience and are therefore representing them. The majority of SAP Fiori apps are web-apps built using SAPUI5 as UI technology. SAPUI5 in turn is based on HTML5 and can be consumed on every device using a Web browser. For developing SAPUI5 applications, SAP offers SAP Business Application Studio (running on SAP Business Technology Platform) and SAP Fiori tools - Extension Pack for Visual Studio Code.

As of AS ABAP 7.40 SAP Fiori Launchpad – which is the entry point to SAP Fiori apps on mobile or desktop devices – is part of every SAP AS ABAP.