A method and apparatus for measurement of service disruption interval is described. The apparatus may include may included a setting component, a generating component, a first output component, a receiving component, a service disruption start time designator, a settling start time designator, a settling period designator, a service disruption end time designator, a service disruption interval designator, a second output component, and a memory component. In general, a test set consistent with the described embodiments may continuously send test traffic through a network under test (“NUT”) and monitor the traffic output from the NUT. The test set may be configured to detect the start of a service disruption and to detect when the service disruption has been cleared. Based on these two pieces of information, the test set may determine and report a service disruption interval.