As per TOGAF standard, it is IT Architect role that connects the IT with Business,
In order perform this role, having a a technical knowledge of product "A" for example is usually not sufficient for this role owner. One also need to know the costs associated, and licensing model of the solution plus at least some knowledge of the competing products. Without grip on these it is NOT possible to propose viable solution based on context of costs and market segment of the product overall.
TOGAF process to the development of architecture is very straightforward,
Having designed Exchange Architecture for so many organizations, today decided to upload a common print for reference for all