What information is described by an Enterprise Arc

Question

I'm tasked with building a set of Architectural Diagrams to share with a third party. Most have been pretty familiar, but the request for an Enterprise Architectural Diagram has me a bit stuck. I'm not exactly sure what information this particular diagram is supposed to convey to the reader.

Answer 1

I don't think that the term "Enterprise Architectural Diagram" has a well-defined meaning, while "Enterprise Architecture" refers to the attempt of holistically describing an enterprise, including its IT and application systems, as a socio-technical system. Making such a complete description of an enterprise (in the form of a bunch of diagrammatic and textual models and accompanying documents) is certainly an important, but possibly too ambitious, goal.

There are a number of proposals how to make an "Enterprise Architecture". The most prominent historical proposal is the Zachman Framework. A more recent proposal is ArchiMate, which is a standard of the Open Group. In all these proposals, a number of stakeholders and their viewpoints have to be identified such that a set of viewpoint-specific models at different levels of abstraction help to describe all relevant aspects of the enterprise, including all sorts of business management and IT issues. Modeling languages used for making these models may include UML and BPMN.

For making some business-level enterprise architectural diagrams with ArchiMate, you could model

1. the stakeholders and their concerns in a Stakeholder View diagram;
2. the organization structure as nested block diagrams, but also in a more traditional way, such as organizational charts;
3. the business functions of your enterprise in a Business Function View diagram.

Answer 2

Neither UML nor SysML defines an Enterprise Architecture Diagram. It might be that there is a clear definition of this diagram type in some other modelling language or framework, but if so I am not aware of it.

Modelling an actual enterprise architecture can be done using TOGAF or some other framework, but that's a pretty massive task (which easily results in dozens or hundreds of diagrams) and certainly not something you either throw in at the last minute, or ask for on a whim.

If they did specify one rather than a set of such diagrams, my guess would be that they're asking for a high-level overview in a relaxed format which mixes different views to provide a kind of "executive summary" diagram. Check out this Wikipedia page, especially what the second example refers to as an "architecture interconnect diagram," that might be what they're after.