Question

Define and describe the function and interrelationship of a drum, drum buffer, and a capacity constraint buffer in CCPM. Use example to apply CCPM to multiple project portfolios by formal step

Answer 1

• A drum is a system wide constraint that sets the beat of the system, effective limiting the entire system or project collections.
• Drum buffer are extra safety that is applied to project immediately before the use of resources so that they will not be used for work.
• A capacity constraint is a safety margin to separate use of same resources by different project schedules.

Explanation:

In terms of a single project, to protect drum from fall idle, it is protected by extra safety margin, the drum buffer. As the organization add more project to it operations, a drum is protected by capacity buffer that differentiate the use of drum from one project to another.