Term Kind Topic What it is
Assumption Register practice Technical Constraints The record of the numeric assumptions a design was sized against, monitored so the architecture announces when its own premises expire.
Technical Constraints concept Technical Constraints The existing estate, skills, licences, contracts and platforms that bound the solution space — inputs to the design, not obstacles to it.
Vendor Lock-In concept Technical Constraints The cost of switching away from a provider, treated as a quantity to be managed deliberately rather than a condition to be avoided absolutely.