Requirements

Functional Requirements:

A functional requirement describes what a software system should do. The functional

requirement is describing the behavior of the system as it relates to the system’s

functionality.An example of a functional requirement would be:

 A system must send an email whenever a certain condition is met (e.g. an order is placed, a

customer signs up, etc).

Non-Functional Requirements:

A Non-functional requirements place constraints on how the system will do so. The non-

functional requirement elaborates a performance characteristic of the system.A related non-

functional requirement for the system may be:

 Emails should be sent with a latency of no greater than 12 hours from such an activity.

Typically non-functional requirements fall into areas such as:

 Accessibility ,Capacity,Compliance

 Documentation ,Disaster recovery

 Efficiency ,Effectiveness ,Extensibility

 Fault tolerance

 Interoperability

 Maintainability

 Privacy ,Portability ,Quality ,Reliability

 Resilience ,Response time ,Robustness

 Scalability ,Security ,Stability .Supportability ,Testability