Järjestelmäkuva

Järjestelmäkuva is a diagrammatic or textual model that outlines the structure, components, interfaces, and data flows of a system. It may describe software systems, hardware deployments, or socio-technical environments, and it is used to communicate system boundaries, responsibilities, and dependencies to stakeholders.

A typical Järjestelmäkuva identifies the system boundary, primary components or subsystems, interfaces and protocols, data stores and data flows, major external actors, and deployment context. It helps teams reason about how parts interact, where data resides, and where changes may have impact.

Notations and approaches vary: examples include UML component and deployment diagrams, data flow diagrams, ArchiMate views, and simple block diagrams. The choice depends on audience and purpose. A Järjestelmäkuva can be created at different levels of abstraction—from a high-level context diagram (the system as a black box) to a decomposition into subsystems and, in larger efforts, to internal structure and behavior models.

Use and benefits: it supports shared understanding among developers, operators, and business stakeholders; aids design decisions, integration planning, and risk assessment; serves as a reference for maintenance and onboarding.

Example: for an online bookstore, the diagram may include a web frontend, authentication service, catalog service, shopping cart, payment gateway, order management, and inventory. Data flows track customer data, product data, and payment information; interfaces include REST APIs and messaging.

Relation to other documentation: Järjestelmäkuva is commonly part of broader architecture and requirements documentation, and is updated as the system evolves.