10.2 Evaluate Architectures and System Conversion
In this section, we’ll cover the migration paths and highlight the key considerations in the decision process.
10.2.1 SAP S/4HANA Migration Paths
The SAP S/4HANA migration process has several options. The first option is to start a totally new implementation of the SAP S/4HANA system, a greenfield approach, where your legacy systems, SAP ERP or not, are treated totally independent to your new SAP S/4HANA.
The second option is to complete a conversion of your current SAP ERP legacy system into SAP S/4HANA.The third option is to complete a total landscape transformation, where a migration of several global SAP and non-SAP transactional systems is complex.
Path 1: New Implementation
In our experience, many SAP ERP implementations in the past 20 years faced technical and functional constraints relevant to the system versions available at that time. After the implementation was live, companies were able to upgrade their systems, from the technical point of view, with the latest software versions that were improved by new technologies.
The functional upgrade of the same systems weren’t that common because of the challenges in disrupting a live system and because businesses were running customized versions that fulfilled their business requirements. Note that the customization was designed based on the business processes of the implemented software version.
If your organization followed a similar implementation pattern, the fresh, clean, and new SAP S/4HANA implementation is a feasible option and you should follow the migration strategy analysis proposed in Section 10.1, Migration Strategy.
If the analysis shows that your organization requires a more flexible and agile adoption of business changes and that your current heavily customized system processes are preventing that flexibility, an SAP S/4HANA new implementation or a greenfield implementation is a good option.
Other factors may also result in the technical analysis, which will determine that moving your legacy SAP ERP system into SAP S/4HANA will be challenging due to internal custom code developed in the past.
Path 2: System Conversion
If you determine in your migration strategy analysis that there is a balance between the technology developed by your organization using your legacy systems, and these systems are running accordingly to unique business processes of your organization, the technical migration strategy determines that the risk of migrating your current systems into SAP S/4HANA is manageable.
The SAP Activate methodology and different SAP tools to support this conversation are available, depending on your current systems and target deployment options.
The SAP Activate methodology covers the SAP S/4HANA system conversion best practices, guided configuration, and defined methodology.
Path 3: Landscape Transformation
The third option of a total landscape transformation is suitable for organizations with a large global systems landscape with complex business operations, that require both, a fast modernization of core processes and require the integrity of heavily customized processes at the system, or scenarios, levels.
One example of this approach is the implementation of SAP S/4HANA Central Finance, which integrates with other SAP and non-SAP transactional systems.
Some systems also require a consolidation of one or many various SAP S/4HANA systems.
When converting your SAP Business Suite system to SAP S/4HANA, your conversion path depends on the level of your source system. A source system is the current SAP ERP system within organization, and the target tystem is the new system to be installed.
SAP S/4HANA Systems Available
The technical prerequisite before starting your conversion is to have your SAP Business Suite as SAP ERP 6.0 EHP 7.0. The SAP ERP system could be running already in an SAP HANA database or any other traditional relational database.
Table 10.3 shows the different releases of SAP S/4HANA.
Note
The SAP S/4HANA system has had several releases since its first version—the SAP S/4HANA Finance Edition 150.
Table 10.3 SAP S/4HANA Releases
The decision to go to SAP S/4HANA Finance first depends on the specific business needs of the corporation; however, this isn’t a prerequisite to migrating directly into the SAP S/4HANA system.
SAP Start Release and Target SAP S/4HANA Release
If your company is a new start-up, or your legacy transactional system isn’t an SAP Business Suite business or an SAP S/4HANA system, your path is to start the implementation of the SAP S/4HANA 1709 system first. Table 10.4 explains the conversion path from your start release system to SAP S/4HANA 1709.
| Start Release | Target Release | Available |
|---|---|---|
| SAP ERP 6.0 EHP 7 or EHP +7 | SAP S/4HANA System 1709 | September 2017 |
| SAP S/4HANA Finance 1503 | ||
| SAP S/4HANA Finance 1605 | ||
| SAP S/4HANA 1610 | ||
| SAP S/4HANA 1709 |
Table 10.4 Identification of Possible SAP Source Systems to be Converted to SAP S/4HANA
10.2.2 Integration of SAP S/4HANA to Cloud Solutions
The SAP S/4HANA platform provides innovated and tightly coupled solutions that support the integration of business scenarios, business processes, and cloud solutions.
SAP S/4HANA is offered in two different deployment options. The first option is on-premise SAP S/4HANA, and the second option is SAP S/4HANA Cloud. These two deployment options support the integrations with different cloud solutions. The following SAP cloud solutions are tightly coupled:
- SAP Ariba Catalog
- SAP Hybris Marketing Cloud
- SAP Fieldglass for Labor
- SAP Concur Travel
- SAP SuccessFactors Employee Control
The SAP S/4HANA architecture equally supports non-SAP cloud solutions such as Vertex for tax solutions.
10.2.3 SAP S/4HANA Integration Capabilities
SAP S/4HANA can be configured to integrate with Software-as-a-Service (SaaS) solutions using one of the available options shown in Figure 10.5.
Figure 10.5 SAP S/4HANA Integration Capabilities
SAP Process Orchestration
SAP Process Orchestration empowers your organization in the automation and optimization of your business processes. It supports the implementation of simple workflows to develop your custom process applications that may exchange data from SAP and non-SAP applications.
SAP Process Orchestration is Java only and provides an infrastructure tool that is based on the activities process flow of your SAP S/4HANA business process activities, the data types that are needed by each business step, and the relevant interfaces to connect to external systems.
SAP Process Orchestration combines the use of business process management (BPM) to model and execute your processes in a fast and flexible way, SAP Process Integration (SAP PI) to manage the integration across heterogeneous environments, Enterprise Service Repository (ES Repository) to model and specify development objects to be implemented at various level of detail. Business rules management (BRM), that allow your organization to automate decisions by using business rules. SAP Gateway as an OData provisioning, and finally business-to-business (B2B) collaboration to collaborate with business partners.
The main components of SAP Process Orchestration are the Advanced Adapter Engine Extended (AEX), BPM, and BRM, as follows:
-
AEX
AEX provides the connectivity capabilities of the Advanced Adapter Engine (AAE) and also the ES Repository and Integration Directory that allows your technical team to set up integration scenarios. -
BPM and BRM
The two tools allow you to design, execute, and monitor business processes. You’ll be able to tailor your business processes with the new functionality provided by your cloud solutions by enabling central process execution using the Java-enabled process engine.
The processes are enabled using integration business rules and intuitive provisioning interfaces for business users.
SAP Cloud Platform Integration Services
This platform supports the end-to-end process integration across cloud-based and on-premise applications, such as messages exchanged between the source and target systems.
The SAP Cloud Platform runs a cluster of virtual machines to ensure that data related to different customers connected to the cloud is isolated. Messages are processed, transformed, and routed between all systems in the platform. The connectivity is supported using IDocs, SFTP, SOAP/HTTP, SAP SuccessFactors, OData, and HTTPS. The SAP Cloud Platform has security features such as content encryption and certificate-based communication as well.
The integration lead times and complexity are reduced because the SAP HANA Cloud Platform offers predefined and ready-to-use prepackaged integration content without the need of additional hardware or specific integration skills.
SAP Web Services
Web services help you convert your system in a service-oriented software architecture. Each web service is an executable unit called in a heterogeneous system landscape and it’s restricted to a single host. The technology operates on simple caller-receiver methods.
Each output is determined based on the given input parameters. The web service processes and determines the output that relies on the given input parameters.
Web services are available in ABAP and Java flavors, and they are defined for the ABAP engine and the J2EE engine development environments. In addition, interoperable SOAP runtime requests that use the Internet Communications Framework (ICF) are part of the development framework.