Carrier grade
Carrier grade (German: operator level ) is an informal specification for the reliability of a system. It is used in particular in the area of network components for computer and telecommunications networks and means that the device fails on average for less than 5 minutes a year. This corresponds to an availability of 99.999% of the total time, which is often referred to as five nines .
The term carrier grade expresses the fact that active components in telecommunications networks can only be used by the network operators (the carriers ) if they have a correspondingly high level of failure safety. In general, network operators have the highest demands in terms of reliability. With company servers or even workstation computers , expectations are usually much lower.