Types of Requirements Functional Requirements define what functions need to be done to accomplish the mission objectives ■ Performance Requirements define how well the systems needs to perform the functions ■ Constraints are requirements that can not be traded off with respect to cost,schedule,or performance Interface Requirements Environment Requirements ■ Other-illities requirements includes:human factors,reliability requirements,safety requirements CLGO System Engineering by J.J.Gao 10+ - System Engineering by J. J. Gao 10 Types of Requirements  Functional Requirements define what functions need to be done to accomplish the mission objectives  Performance Requirements define how well the systems needs to perform the functions  Constraints are requirements that can not be traded off with respect to cost, schedule, or performance  Interface Requirements  Environment Requirements  Other-illities requirements includes: human factors, reliability requirements, safety requirements