Degradation

In telecommunication, the term degradation has the following meanings:

1. The deterioration in quality, level, or standard of performance of a functional unit.

2. In communications, a condition in which one or more of the required performance parameters fall outside predetermined limits, resulting in a lower quality of service.

Note: Degradation is usually categorized as either "graceful" or "catastrophic."

Source: from Federal Standard 1037C