Introduction to ERP and EAI - Basic Understanding of SAP PI

Objective of this article

The objective is to article to cover the concept of ERP and EAI for the beginners. Please note that this article is for someone who is new into the world of Business Application and Integration.

ERP - Enterprise Resource planning:

As per the definition, Enterprise resource planning (ERP) is business management software. in general a suite of integrated applications, that a company can use to collect, store, manage and interpret data from many business activities, which would include Product planning, cost, Manufacturing or service delivery, Marketing and sales, Inventory management, Shipping and payment etc.

Lost with this? Don't worry, Let us take couple of steps back and try to understand. Think of any Business, let us take an example of "Amul" and consider the product of Butter. (Why Amul? Well it just came into my mind and being from India, why not take an Indian company?) Now in order from a business to run smoothly different sector of the business has to run together and share and collaborate with the data. This would start with understanding the demand of the product, accordingly plan the purchase of raw materials, hence generating the Purchase Requisition and Purchase Orders for the same and finally getting the Invoice and paying the Vendor.

Just this much would include so many different department to work together and share data and information. You might say this would be a very high level database programming consisting of thousands of table and lots of front-end pages. Well, ERP says, they have already planned this and created a software which is ready to give you a product which you can use for your business with minimal customization.

Now that we know a bit of ERP, Lets know who is SAP? SAP SE (Systems, Applications & Products in Data Processing) is a German software company , head quartered in Walldorf, Germany, who is the creator of probably the most famous ERP package used currently known as SAP ECC (ERP Central Component). They are considered to have over 282,000 customers in 190 countries.

SAP ECC has multiple subpage including Human Resource, Material Management, Sales And Distribution, Finance and Controlling, all integrated into a software solution that incorporates the key business of the enterprise. Along with the ECC, SAP also create a product called NetWeaver Suite, of which SAP PI is a part.

EAI - Enterprise Application Integration:

Enterprise application integration (EAI) is the use of software and computer systems' architectural principles to integrate a set of enterprise computer applications. By that, what we are trying to say, is no business can run and work alone. For example, Amul has let us say 750 employees, and Amul need to pay Salary to them every month. The information about the salary has to go to the Bank so that they are paid. Hence Data from one Business (Amul) flows to another Business (State Bank of India). This is called integration of data and this is where EAI is used.

SAP NetWeaver Process Integration (SAP PI) is SAP's enterprise application integration (EAI) software, a component of the NetWeaver product group used to facilitate the exchange of information among a company's internal software and systems and those of external parties. Thus, SAP PI is an integration broker.

Big Question: Why Middleware / EAI

The first question that comes to your mind when you start going into a training of SAP PI is Why do you need a Middleware? 

Understand that no business can run alone. Let us again use an example, Consider a business of Apparel, Say "Louis Vuitton", There would be multiple other business interacting with them. e.g. 

    A business who would supply the raw material, 

    A business of Retail and point of sales like "Macys" 

    A bank say "Bank of America" who would be paying salary. 

Now all business might not use the same software and same applications. Hence you would need someone who can understand and talk multiple applications. Middleware does this for you. It is just like a multilingual who would talk the two languages. 

That being said, is not the sole purpose of using a Middleware. We would try to understand the different purposes now:

Single Point of Communication.

Consider this as 5 different systems interacting with each other.

Now Consider, You get another system into the business who would need to interact with others.

On the other hand, if there is a Middleware, This is how it would look like.

So, with a Middleware it is always easier to add or remove systems from the landscape.

Data Translation.

Consider there are 2 systems, and you want to write data into them. 

    System 1: Understands and work with a Comma Separated Flat File. 

    System 2: Understands SQL and work with a Relational Database Management System. 

Now in system 1 Data would look something like this: 

Id,FirstName,LastName,Designation,Department

101,Andy,Robin,Manager,Sales

102,Maria,Cramer,Analyst,Production

But in system 2, Data would look something like this.

INSERT INTO table_user VALUES (101,A Robin,Manager,Sales),(102,M Cramer,Analyst,Production); 

Middleware would take care of translating data between different system the way they understand. Note that it is not only that a CSV is converted into a SQL, but there are specific field level operation performed.

Data Routing.

Another important aspect of using Middleware is routing.

In case you have a message which has data that need to go to multiple location, the Middleware can manage to split the data and then route to the corresponding receiver. If you see the above example, the data is being sent out of SAP ECC which consist of Material and Plant Combination, and the Middleware take care of routing correct data to correct plant.