Just a tribute to Jack van Hoof, who provided a GREAT primer on intermediation, EAI, and Canonical Data Models in his blog post. If you have ANY questions about what a canonical schema is, what a canonical data model is, or why in the world architects keep using the word “canonical,” then you should read this post.
Excellent Primer on Canonical Data Models
About the Author: Nick Malik
President of Vanguard EA, an Enterprise Architecture consulting firm in Seattle focused on the Pacific coast of the US. Nick has over 30 years of professional experience in management, systems, and technology. He is the co-author of the influential paper "Perspectives on Enterprise Architecture" with Dr. Brian Cameron that effectively defined modern Enterprise Architecture practices, and he is frequent speaker at public gatherings on Enterprise Architecture and related topics. He coauthored a book on Visual Storytelling with Martin Sykes and Mark West titled "Stories That Move Mountains".