Topic 1 – Stack overview

The goal of this blog post is to understand the importance of the layers of the enterprise information technology stack.

The elements of Enterprise Architecture are set up in four layers: Business Architecture Layer, Data Architecture Layer, Application Architecture Layer and Technology Architecture Layer. We’ll look at each stack to see the importance of each layer. An enterprise architecture (EA) assists organizations with understanding the structure of the enterprise and how it works. This “map” of the enterprise provides a plan for business and technology change.

In the Business Architecture Layer there are different strategies: Strategy maps, goals, corporate policies, Operating Model Functional decompositions (e.g. IDEF0, SADT), capabilities and organizational models Business processes Organization cycles, periods and timing Suppliers of hardware, software, and services.

In the Data Architecture Layer, there are stacks of physical data: Metadata – data that describes your enterprise data elements Data models: conceptual, logical, and physical.

In the Application Architecture Layer, there are stacks of software and programs: Application software inventories and diagrams Interfaces between applications – that is: events, messages and data flows Intranet, Extranet, Internet, ecommerce, EDI links with parties within and outside of the organization.

In the Technology Architecture Layer, the focus in on infrastructure and hardware: Hardware, platforms, and hosting: servers, and where they are kept Local and wide area networks, Internet connectivity diagrams Operating Systems Infrastructure software: Application servers, DBMS Programming Languages, etc.

Interstingly enough, and while it’s not a big surprise, there is a fifth layer working up in the industry. Security Architecture, which is defined by Wikipedia as “the artifacts that describe how the security controls are positioned and how they relate to the overall Enterprise Architecture”. We will likely look at this in more depth in later posts.