The cloud (cloud computing) is becoming increasingly important in the economy. Due to the numerous possibilities that arise from the use of a cloud, more and more companies are dealing with this topic.
A major problem, especially for German companies, is data protection. Sensitive data must not be loaded into the cloud and should continue to be managed and protected independently. Many companies rely on their existing infrastructure and will not migrate it completely to the cloud. This may be for legal, corporate policy or strategic reasons.
Nevertheless, the cloud offers numerous functions which companies would like to integrate into their existing infrastructure or applications in order to optimize them (see [9]).
On the other hand, it often takes employees in the corresponding development departments too long for the system administrator to set up the required programs and users. Often, the required hardware or software is not available and must first be procured, or internal processes exist that slow down or even prevent procurement or setup. Thus, fast and agile development is not possible.
To counteract this, developers often fall back on an existing cloud infrastructure in order to be able to quickly build a prototype. This is quickly ready for use and does not cause a large financial burden for the company (see [22] and [11]).
In addition, the cloud can save costs that would otherwise have been spent on the provision of resources in order to circumvent bottlenecks that occur. Furthermore, software can be used in the cloud that is not even available in the company or the know-how about it does not exist.
It becomes problematic when a prototype that has been built has been able to convince the committees and is now to go live. Most prototypes work with exemplary data, which must be replaced immediately by real data from the data center. However, migration to the hardware and software in the data center is not always possible without effort. Besides, the application already works and should not be developed a second time unnecessarily.
There are also applications or data stocks in databases on the mainframe that are to be made available to a cloud application as a service, for example to provide smartphone apps for employees.
The goal of this work is to develop an architecture that can securely integrate an application built in the cloud into the existing infrastructure.