architecture principles notes

When I watched a presentation by Ebay architect about Ebay architecture principles, I was thinking about how could we figure out what architecture principles we could use in my specific project cases. After all, architecture principles vary from company to company and from project to project. So what does it derive from? After reading some resources, here is my notes.

1. what?

Before we go further, we'd better make clear what the architecture principles are. Here is a definition from TOGAF's enterprise architecture framework:

Architecture principles are a subset of IT principles that relate to architecture work. They reflect a level of consensus across the enterprise, and embody the spirit and thinking of the enterprise architecture.
......
Architecture principles define the underlying general rules and guidelines for the use and deployment of all IT resources and assets across the enterprise. They reflect a level of consensus among the various elements of the enterprise, and form the basis for making future IT decisions.

Each architecture principle should be clearly related back to the business objectives and key architecture drivers.

It seems way too dogmatic. Here are the guts:

• They are IT principles.
• They are general guidelines and rules of utilizing IT resources.
• They should be well aligned with business objectives.
  

Here is the components an architecture principle usually contains:

• Name: representative name with clear meaning
• Statement: description of unambiguous fundamental rule
• Rational: highlight business benefits, point out the relations to business principles and relations to other architecture principles, and how to weight them in context
• Implication: requirements from both IT and business to carrying out the principle in terms of resources, cost, activities and cost. It's about impact and consequence.
  

Here is an architecture principles example from Example Set of Architecture Principles from TOGAF's enterprise architecture framework. Another example is NIH enterprise architecture. Maybe this example is more technology oriented.

2. how?

According to the above interpretation of what, we could only derive these architecture principles from business objectives. Here is the method of running a workshop to draw up them. The key points are:

• Identify Strategic Objectives
• Record Strategic Objectives
• Identify Architecture Principles
• Explain Architecture Principles
• Prioritize Architecture Principles
• Show Prioritization Results

reference:

1. http://it.toolbox.com/blogs/enterprise-solutions/running-an-architecture-principles-workshop-12581
2. http://it.toolbox.com/blogs/enterprise-solutions/sample-architecture-principles-workshop-agenda-12598
3. http://www.opengroup.org/architecture/togaf9-doc/arch/
4. http://www.bredemeyer.com/HotSpot/20040428EASoapBox.htm
5. http://enterprisearchitecture.nih.gov/ArchLib/Guide/EnterprisePrinciples.htm
6. http://enterprisearchitecture.nih.gov/About/Approach/Framework.htm
8. http://blogs.msdn.com/architectsrule/archive/2008/04/22/reference-architecture-principles.aspx