S S symmetry Article Framework for a Symmetric Integration Approach Mihaela Muntean 1,* , Claudiu Brânda¸s 1 and Tanita Cîrstea 2 1 Business Information Systems Department, Faculty of Economics and Business Administration, West University of Timisoara, 30023 Timisoara, Romania; [email protected] 2 SAP Romania, 300011 Timisoara, Romania; [email protected] * Correspondence: [email protected]; Tel.: +40-742-089-058 Received: 26 December 2018; Accepted: 5 February 2019; Published: 14 February 2019 Abstract: An Application-to-Application integration framework in the cloud environment is proposed. The methodological demarche is developed using a data symmetry approach. Implementation aspects of integration considered the Open Data Protocol (OData) service as an integrator. An important issue in the cloud environment is to integrate and ensure the quality of transferred and processed data. An efficient way of ensuring the completeness and integrity of data transferred between different applications and systems is the symmetry of data integration. With these considerations, the integration of SAP Hybris Cloud for Customer with S/4 HANA Cloud was implemented. Keywords: application integration; data integration; data symmetry; Open Data Protocol (OData) service 1. Introduction Ensuring the quality of data integration in cloud-based hybrid systems and applications is an important issue both in business and in data science. Integration frameworks are focused on data integration or application integration. Data integration implies the transfer, replication, and transformation of data from one place to another (from one application to another)—ignoring application or business logic. Application integration is defined as linking systems together at the application/business logic level. According to Tibbetts (2011) “neither method of integration is superior or inferior to the other—it simply depends on the need” [1]. Application integration in the business environment has grounded the widely used Enterprise Application Integration (EAI) paradigm, which is sustained by dedicated systems, e.g., Enterprise Resource Planning (ERP), Customer Relationship Management (CRM), Supply Chain Management (SCM) systems, or other enterprise-integrated applications. However, various integration projects in organizations nowadays employ both types of integration frameworks. According to Linthicum (1999), EAI conducts the strategic utilization of company data and technology for greater efficiency and profit [2]. Four types of integration are identified: Data-level, application interface-level, method-level, and user interface-level—the last three together are supported by the business model level [2]. The EAI architecture has been transposed into the cloud and is supported by cloud computing infrastructure and services [3,4]. Cloud applications integration is facilitated by various classes of Application Programming Interfaces (APIs), predefined or developed, such as application, data service, or data set APIs. Cloud services provide access to server infrastructure and resources that are managed by a provider, e.g., Infrastructure as a Service (IaaS), Platform as a Service (PaaS), and Software as a Service (SaaS). According to Deloitte practitioners [5], to integrate cloud applications, the following integration approaches are applicable: Cloud-to-Cloud; Cloud–Integrator–Cloud; and Cloud–Cloud–Cloud (Cloud-Cubed) integration. Symmetry 2019, 11, 224; doi:10.3390/sym11020224 www.mdpi.com/journal/symmetry Symmetry 2019, 11, 224 2 of 10 Symmetry 2018, 10, x FOR PEER REVIEW 2 of 10 A primary issue in integration processes is the level of data quality. Corrales (2018) synthesized A primary issue in integration processes is the level of data quality. Corrales (2018) synthesized the diverse approaches regarding data quality issues [6]. An integration approach based on symmetry the diverse approaches regarding data quality issues [6]. An integration approach based on ensures the completeness and integrity of data transferred between different applications and systems. symmetry ensures the completeness and integrity of data transferred between different applications Weyl (1983) presented the importance of symmetry in science and other domains [7]. Murtagh (2009) and systems. Weyl (1983) presented the importance of symmetry in science and other domains [7]. underlined the role of symmetry in Data Analysis and Data Mining [8]. In the context of the widespread Murtagh (2009) underlined the role of symmetry in Data Analysis and Data Mining [8]. In the context use of cloud-based hybrid applications and the importance of symmetry in the quality of the data of the widespread use of cloud-based hybrid applications and the importance of symmetry in the integration process, we considered it necessary to develop a framework for the symmetric integration quality of the data integration process, we considered it necessary to develop a framework for the of applications. symmetric integration of applications. 2. Framework2. 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Symmetry 2019, 11, 224 3 of 10 Symmetry 2018, 10, x FOR PEER REVIEW 3 of 10 Figure 2. Integration framework for SAP Hybris CloudCloud forfor CustomerCustomer (C4C)–S/4HANA(C4C)–S/4HANA Cloud (S/4)(S/4) [ [77]].. Best practices in in integration integration methods methods point point out out three three alternatives: alternatives: Application Application-to-X-to-X users users (A2X) (A2X),, using a SOAP SOAP-based-based web service in synchronous execution;execution; Application-to-ApplicationApplication-to-Application (A2A), (A2A) using, using a aSOAP-based SOAP-based web web service service in in asynchronous asynchronous execution;execution; andand OpenOpen DataData Protocol using a REST REST-based-based web service inin synchronoussynchronous executionexecution [ 11[11––1313].]. The The OData OData service, service, metaphorically metaphorically named named the the “SQL “SQL