Do you feel like there is a complete overhaul of the SAP middleware every 3 days? Ever wondered what are the differences between XI, PI, and PO? Well, you are not alone! There have been major changes to SAP middleware XI/PI/PO in its lifetime. From the first introduction of SAP XI in 2002, SAP has completely changed the architecture with their major version upgrades.
As an integration consultant, you have to not just keep up with the new PI/PO technology and architecture changes, but be ready to deal with hundred new abbreviations that come with it. IE, IS, IR, ESR, AE, AAE, AEX, ccBPM, NWBPM?! Do not worry, I am not trying to confuse you more with these abbreviations. Not only will we compare the differences between SAP eXchange Infrastructure (XI), Process Integration (PI), and Process Orchestration (PO), but also look at different components that belong to each version. Also, we will compare new components available in SAP PO and what components have become obsolete in PI/XI versions due to the introduction of java only PO architecture.
Moreover, we will talk about the features of the SAP Integration Suite and SAP Cloud Platform Integration.
For us to understand the differences between XI, PI and PO, first, we need to look at the main functionaries of middleware,
What is Middleware:
Connectivity: Which protocol to use – SOAP, FTP?
Routing: Who are the receivers of the message – Multiple receivers? Condition-based routing?
Transformation: What kind of conversion or mapping is required? XML to text?
Runtime: messages monitoring and security
Workflow (BPM): How to execute a series of steps? Integration scenario with a Purchase Order approval process?
SAP has been able to cover all these areas successfully with SAP PI/PO middleware solution.
Overview of SAP Middleware Versions:
The first SAP eXchange Infrastructure (XI) was introduced in 2002 with version XI 2.0. This was a dual-stack option with ABAP and Java stacks. After a few versions of XI, SAP introduced SAP Process Integration (PI) 7.0. PI single stack only installation option was introduced with PI 7.3 in 2010. Finally, in 2011 SAP introduced PO (Process Orchestration) with version 7.31.
To understand the differences between these versions, let’s look at the major architecture changes of each.
SAP eXchange Infrastructure (XI) Architecture Overview:
SAP eXchange Infrastructure (XI) contains Adapter Engine (AE), Integration Engine (IE), and Business Process Engine (BPE). It was installed on a dual stack Netweaver installation with ABAP and Java stacks.
AE – Adapter Engine
As the name suggests, the main purpose of this component was to provide connectivity functionality. Adapter engine provided capabilities of talking to different communication protocols using different adapters.
IE – Integration Engine
SAP XI component which was responsible for transformation and routing of the messages. Integration Engine also provided a runtime to the message communication. In XI heavy message processing was done through IE as each message was routed, transformed and executed by this component.
BPE – Business Process Engine
The engine which executess ccBPM (Cross Component Business Process Management) workflows. ccBPM is based on Business Process Execution Language (BPEL) and required a dual-stack installation as its runtime environment was on Web AS ABAP.
Drawbacks and Challenges with eXchange Infrastructure (XI):
One major drawback of XI is inefficient performance due to back and forth communication between components. Also due to the dual-stack architecture and multipole components, message persistence impacted the performance.
SAP Process Integration (PI) Architecture Overview:
With SAP introducing Advanced Adapter Engine (AAE), PI was able to process messages end to end without Integration Engine (IE) runtime. This reduced the cross-communication between components and improved performance massively.
AAE – Advanced Adapter Engine
AAE has capabilities to handle routing, transformation, and connectivity which were segregated into different components in SAP XI. Integration Configuration Object (ICO) was introduced for design time instead of traditional XI objects such as sender agreement, receiver determination, and receiver agreement. ICO made it possible to connect, transform and route messages in AAE without Integration Engine (IE) runtime. Also, dual-stack message persistence was eliminated since ICO scenarios were executed independently by AS Java.
Drawbacks and Challenges of PI with AAE
Although PI installation with AAE enhanced performance in comparison with XI, still improvements were needed to extend connectivity and performance. AAE could only handle a limited set of connections and still required IE runtime for development and administrative purposes. Plus, the RNIF adapter and the CIDX were not available in AAE. Also, earlier versions of AAE did not include iDoc and HTTP adapters since they belonged to the ABAP stack. Moreover, BPE still required ABAP stack for runtime as it was ccBPM. As you notice, although performance was improved compared to XI, SAP couldn’t completely decouple the need for Integration Engine (IE).
B2B add-on was also introduced to PI with versions PI 7.1. B2B comes with a set of B2B protocol adapters, converter modules, and B2B infrastructure services for serving the EDI integration needs of most industries.
AEX -Advanced Adapter Engine Extended
Finally, with SAP PI 7.30 version SAP eliminated the need for Integration Engine (IE) and introduced the Advanced Adapter Extended (AEX). AEX is a single-engine which includes Enterprise Service Bus (ESB), Integration Directory (ID), and AAE capabilities. With AEX, PI became a Java AS-only installation and SAP completely decoupled the ABAP stack. Also with PI 7.3 SAP introduced the iDoc_AAE adapter and http_AAE which run on Java. The complete removal of the ABAP stack is a major change in the SAP PI architecture.
Drawbacks and Challenges of PI with AEX
Although PI with AEX improved performances by completely decoupling the ABAP stack and the need for Integration Engine (IE), it did not include Business Process Management (BPM) capabilities.
SAP Process Orchestration (PO) Architecture Overview:
To overcome all these challenges with PI, SAP released Process Orchestration which was a Java-only installation. Yes! No ABAP stack installation was available from PO 7.31. Plus, with the new PO version SAP has added fully functional Netweaver Business Process Management (NW BPM) and Business Rule Management (BRM) which were fully executable on Java. Therefore, Process Orchestration (PO) is a combination of Process Integration (PI) with AEX, Business Process Management (BPM), and Business Rule Management (BRM) which only runs on Java.
NW BPM – Netweaver Business Process Management
Unlike ccPBM, NW BPM runs on a Java-based environment called CE (Composite Environment). Also, NW BPM uses Business Process Model Notation (BPMN) language while ccBPM uses Business Process Execution Language (BPEL). Although ccBPM design time was on ABAP stack, you require Eclipse-based tool NWDS (Netweaver Development Studio) for NW BPM. Even if you have extensive experience in ccBPM, you need to start learning NW BPM from scratch.
BRM – Business Rule Management
Business Rule Management (BRM) contains modeling capabilities targeting business analysts. Rules are owned by LoB, not by IT.
What is SAP Integration Suite and Cloud Platform Integration (CPI)
SAP Integration Suite was formally known as SAP Cloud Platform Integration Suite (CPI). SAP Integration Suite is the Integration-Platform-as-a-Service offering from SAP. Organizations can acquire SAP Integration Suite features on a subscription basis. Since the integration platform services can be accessed via the internet, it greatly reduces the initial implementation costs for hardware and IT resources.
Following are the main features of SAP Integration Suite;
- Cloud Integration
- Open Connectors
- API Management
- Event Mesh
- Integration Advisor
SAP Integration suite (CPI) is not a newer version of SAP PO. It is a new integration platform provided by SAP to address cloud-based integration requirements.
Cloud Integration feature provides a platform to build, deploy, and manage end-to-end integration scenarios in cloud-to-cloud, cloud-to-on-premise, and on-premise-to-on-premise domains.
Additionally, SAP has provided more than 2000+ prebuilt integration flows on A2A, B2B, and B2G processors that can be deployed with the minimum development effort.
The open connector capability of the SAP Integration Suite standardizes the connectivity to third-party cloud applications. SAP has provided more than 160+ pre-built connectors to none-SAP cloud applications such as Shopify, ADP, SalesCloud, Workday, etc. Developers can easily reuse these prebuilt connectors to establish connections to third-party cloud applications. You can find a full list of open connectors here.
API Management is the feature that provides a platform to build, analyze, publish and monetize APIs.
The event mesh makes use of event-driven architecture for integration. This greatly reduces having to have peer-to-peer connections. Organizations have the option to publish their business events in a data lake or data queue for multiple data receivers to consume.
To conclude, SAP PO contains all the functionalities of PI, plus BPM and BRM in a single Java stack. I hope you were able to visualize the evolution of SAP middleware. By looking at the history of changes to SAP middleware architecture from XI to PI to PO, you can see the reasoning behind these changes.
Additionally, we discussed the features of SAP Integration Suite and CPI.
If you have any more questions comment below!