In most cases, constraints are usually controlled by Electrical Engineers, and they drive the rules and requirements for critical nets from their schematic capture package. This is usually the most effective way of managing constraints, as it allows an organization to assign a point of control for maintaining the integrity and intention of a design concept. The down side of this approach is that if any design changes occur, or if critical nets do not meet routing requirements, there can be a significant increase in the potential for board defects. But there is another way – having the flexibility to utilize a Constraint Management tool to pass constraints at ANY point within the design phase, and to report and track changes made.
