Suspension criteria in the context of software testing means suspending the complete or part of the testing activities whereas resumption criteria imply resuming the previously suspended activities.
The reason behind suspension criteria are quite a few such as – one may lack the availability of external dependant components during execution, or when a defect is detected which may restrict the testing process to proceed further.
On the contrary the testing activities are resumed as and when the dependant components are made available or the defect is successfully resolved.
For instance, suspension criteria follows a suspension approach in which if a given input for a program does not generate the same results as that of a parallel program, testing is suspended.
Software development can't be a success without an efficient planning. Thus it is essential to plan the testing process that is to be resumed. User acceptance test execution involves taking into consideration future development releases along with the business releases.
IEEE829 - According to this we need to specify the criteria that is used to suspend all or a part of the testing activity on the items of testing that is associated with the plan. Also specify the testing activities that must begin on resumption. It is important to understand that if a defect is detected at a point after which the testing shall resume proves to be of no use, then applying the resources on testing will be futile. One needs to specify the reason for stopping the test activities and define the acceptable level of defects that allows the testing process to surpass those defects. Few defects may arise on resuming the test activity. Those are the hidden defects that were somewhere ignored earlier.
Suspending a testing process takes place when there is a need to fix a defect. So there needs to be a strategy by which we are in a position to decide whether to resume the suspended testing process or not, because retesting is again a matter of time. One should make sure that the resources of an organisation are not wasted unnecessarily.