Introduction to PEGA

PEGA is an Enterprise software product created using Java concepts, allowing developers to build applications faster. The primary focus is on building applications by providing Intelligent Business Process Management Suites. It offers an Integrated Development Environment (IDE) to develop applications where business and IT can collaborate to work together on a common understanding and reduce process gaps.

Architecture

Pega Platform is organised into multiple areas. Each area focuses on a specific part of the platform, such as User Interface, Security, Case Management, Configuration Studios, and so on.

Let’s now understand the Pega Architecture, focusing specifically on the layers below.

• Kernel Layer is the bottom layer. All the other layers build on what is in the Kernel Layer. Among other things, the Kernel Layer handles the hardware and deployment abstraction. This means that the kernel layer interacts with all the different types of supported hardware (such as Mainframes, Windows, or Sun). It takes care of all the variations between them and presents a single unified interface to the layers above it.

• Foundation Layer provides the engine’s ‘secret sauce’ functionality, which we’ll talk more about later. This layer includes such things as code generation and the clipboard.

• Execution determines what logic is executed and under what context. Among other things, the execution layer handles security, and runtime interactions with the engine.

• Application Layer is a collection of Java modules that support the Platform and the strategic applications.

• Rule Layer provides business logic configuration for application development. This layer is implemented entirely as a collection of rules. Notice that on the left, it indicates how each layer is implemented. Rules for this layer, Java for all the layers below.

The Client is what is loaded on your browser or mobile device to bring the Pega client experience to you. It can be thought of as an entire platform on its own, and for offline usage, it is an entire platform on its own. This layer is implemented in JavaScript, which is typical for Client implementations for most companies.

Pega Logical Architecture

The Pega applications are Java applications and are most commonly deployed as a classic multi-tier JEE application.

• Client Tier is all browser-based, including the design time. Being browser-based allows Pega to support our development and runtime portals for end users. The end-user interface is browser-independent and supports major browsers.

• Application Tier, Pega supports deployment into WebSphere, Oracle, JBoss, and Tomcat. The Pega engine is deployed either as an EAR or a WAR file. The functionality provided by Pega is the same regardless of how the engine is deployed; however, when deployed as an EAR, Pega can take advantage of the EJB container as well as JEE transaction API and JEE security services.

• Data Tier, Pega leverages a relational, application database. The Pega database uses a split schema design. The Model Schema holds all the process models, business rules, user screens, case definitions, and service levels, that define the way your application runs. When users save a change to a process flow, what they’re saving is a record of the Model schema.

The Work schema stores run-time information such as process states, case data, assignments and audit history. The split schema design is used to support solutions that need to be highly available by allowing upgrades and maintenance of the Pega platform to be performed with minimal to zero downtime.

Pega persists data to the Pega database using a hybrid approach that involves both table column data as well as binary streams (BLOBS). This approach allows the application data model to be changed without requiring updates to the repository schemas, remember Build for Change is our goal with this architecture.

The Pega platform provides out-of-the-box Business Activity Monitoring and Reporting capabilities; however, sometimes it is desirable to copy the data into a data warehouse or an analytics system for further analysis. Pega offers the Business Intelligence Exchange (BIX) product, which allows customers to export Pega binary streams into a format suitable for importing.

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Thank you for exploring this topic with us. We encourage you to continue learning and engaging with us, as growth and improvement are continuous processes. If you have any questions or insights to share, please feel free to reach out.

Stay curious and keep striving for excellence.