Linked systems via web service

Which credit manager doesn’t know about it?

You have to make a decision on a credit application for a customer as quickly as possible, because otherwise the sales department might not receive the large order. As a conscientious credit manager, however, you want to get a picture of the situation that is as complete as possible beforehand in order to be able to take all possible influencing factors into account in your decision.

However, the data needed to make a decision is distributed across various systems in the company. The master data is stored in the ERP system, open items can be viewed in the accounting system, outstanding orders in the merchandise management system, sales estimates can be found in the CRM system and last but not least, the DWH allows you to view the course of the last business year. So you would have to log in to five systems to get a complete overview of a customer. Wouldn’t it be more convenient and effective if you could simply call up the data from the other systems from your central work system? “Yes, of course!”, you will probably think now. And you’re right! The retrieval of information from other systems is just one possible scenario for the use of a technology that is becoming more and more popular. Web services.

What is a web service?

First of all, a web service is a form of interface. An interface is a connection between two systems that enables communication or transfer of information. For example, a power socket is an interface that is necessary to transmit electrical power. In the IT world, interfaces are of great importance. They enable communication between both software and hardware components. For example, a USB port on a computer provides a hardware connection to a USB stick.

Although there is no uniform definition of what a web service is, there are characteristics that every web service has:

A web service offers a service over a network
A web service offers an automated data exchange for the use of functionalities
The exchange of data and functionality is independent of the programming language or hardware and can therefore be integrated into different systems
a web service is a pure computer-to-computer communication

Wide range of applications

But web services can do much more than just retrieve data from other systems. For example, if the Web API of application A (e.g. a credit management system) offers a functionality for creating a customer, application B (e.g. a CRM system) can use this service to create a new customer in application A. As an example I would like to describe a concrete case here:

A sales employee creates a new prospect in the CRM system. The work process stipulates that this prospect must undergo a credit check in the credit management system before quotations and payment terms can be defined. There are various alternatives for transferring the data recorded in the CRM system to the credit management system. The sales representative could write an e-mail to the colleague in Credit Management and ask him to enter the prospective customer there as well and to carry out the necessary credit assessment. I would describe this method as the “on foot” method and prescribe it into the last millennium. A more advanced way would be a file-based interface. A time-controlled export determines in the CRM system once or several times a day all new or changed prospects/customers since the last export and creates a file which contains all required prospect data. This data is made available to the credit management system. There, an automatic, time-controlled import of the data takes place and thus the creation of the interested parties. Depending on the export interval, however, there is a certain time delay between the creation of the interested party in the CRM system and the result of the credit check. This is somewhat more advanced than the “on foot” method and corresponds roughly to the technological state of the art of the 2000s. To stay with the image of the means of transport, I would call this the “bicycle” method.

“State of the art”, however, is a method of communication with as little or no delay as possible (near time or real time). Which brings us back to web services.

If web services are so great, why aren’t they used throughout?

That is a good question. First of all, the systems that are to communicate with each other via web service must also be web service-capable, i.e. the system from which data is to be retrieved or to which data is to be transferred must provide appropriate functions. For example, so that a CRM system can retrieve data on a customer from a credit management system, the credit management system must provide a “GetCustomerData” function. A user clicks on a button “Update CM data” in a customer file in the CRM system. The CRM system then sends an enquiry with the customer number of the respective customer to the credit management system. The function “GetCustomerData” determines the data for this customer number and sends it back to the CRM system. This could be a simple communication between two systems.

Thanks to the high standardisation and platform independence of web services, web services can also be used as data interfaces for apps. This makes it possible, for example, to deliver credit management data to a simple sales app on the mobile device of the field service employee at any time. The field staff could also call up current data from the credit management system during a customer visit. “Show me the open items of customer 4711”, or “Show me customers within 50 km of my current location” could be typical requests for this application.

Conclusion

The use of web services in the communication from computer to computer brings many advantages. With the appropriate use of web services, users can consistently work in the central work system they are most familiar with (integrated working). This not only increases the efficiency of the employees, it also increases the acceptance of data from other systems, if one does not have to log into other systems to use them. Last but not least, communication via web services prevents media disruptions, such as those that inevitably occur in the “on foot” communication described above due to the error-proneness of manual intervention.