Summary. This week’s post is about review of core EA concepts and familiarization with new terms: AWS, microservices, virtual machines, containers, SOA, and DevOps.
Background. In this week’s reading blocks for Penn State University’s College of Information Sciences and Technology’s graduate course EA874, Enterprise Information Technology Architecture, assigned readings covered a review of basic EA structure and topics including composable applications and DevOps. I’ll focus this blog entry on review and categorization EA structure review and the next will examine new terms and summarize their application to a strategic business setting.
EA Structural Review and a New Take on the “Stack”. The basic enterprise architecture structure, according to several modern theories, consists of four to five ‘layers’. This starts with technology infrastructure, moves to data and information, up to application architecture, and in many models ends with business or process architecture. A fifth layer sometimes includes strategy as a top layer. Mainstream EA academic publishing usually adds several ‘vertical’ or ‘cross-cutting’ layers which include security and sometimes maintenance functions.
Overview of the ‘Simplified Stack.’ This week’s reading presented a slightly modified approach. While labeled “simplified”, it actually added more layers than those mentioned above, but in what – in my assessment – appear to be a more intuitive way. I prefer this organization to the mainstream Bernard model:
A Simplified Enterprise Architecture Stack
– The Business Operating Model (BOM)
– Business Process Layer
– Capabilities and Services
– Application Landscape
– Data/Information Services
– Technology Services
– Enabling Technology: actual physical ‘tangible’ technology i.e. mainframes, servers, routers etc.
– Value Added Services (VAS) / Hygiene Services: security, Incident management, disaster recovery, system monitoring etc.
Contrasting the ‘Simplified Stack’ with Bernard’s EA Model. In a way, the model offered in this article equates the ‘Strategy’ layer in Bernard’s model with the BOM, and the ‘business’ layer of Bernard’s model with the Business Process Layer; so, in this way, these two sets of layers can be roughly viewed as conceptually equivalent. However, this model adds Capabilities and Services as a separate layer, above Applications and below Business Processes, and that becomes an important distinction in subsequent blog posts as we examine microservices and containers – newer trends in IT. I prefer this model because it pays tribute to these two separate ‘service’ layers, for applications and technology.
Summary for Strategic Relevance. This week’s article highlights the following: “The principal target audience for the visualization of the ‘Stack’ are CTO’s, CIOs, IT Managers, Business Analysts, and Systems Architects.” This is a key point: the importance of summarized EA modeling is to reach an audience in a concise way for executive decision-making. There are intermediate models as well, for which the intended audience are IT and business analysts, and on occasion, an interested IT executive. But our finalized models must be intuitive in order to serve the purpose of informed high-level, cross-functional decision-making.
Sources:
https://dalbanger.wordpress.com/2014/01/20/back-to-basics-the-enterprise-architecture-ea-simplified/