Carrier grade
In telecommunication, a "carrier grade" or "carrier class" refers to a system, or a hardware or software component that is extremely reliable, well tested and proven in its capabilities. Carrier grade systems are tested and engineered to meet or exceed "five nines" high availability standards, and provide very fast fault recovery through redundancy.
Leif Ekman, professor in Telecommunication, states that "Carrier grade" is not a standard or very clearly defined term but, rather, a set of features and qualities that make the product acceptable by a carrier:
The feature set that enables the carrier to utilize the business with use of that equipment. High quality and very good MTBF. Redundancy. Easy and cost-efficient O&M. All Standardized as much as possible
