The Uptime institute works in the data center industry focusing on cost, reliability and energy consumption of computing. They work closely with companies that run data centers to analyse uptime making their knowledge available to companies working in the data center industry. They developed the Tier classification system for rating fault tolerance in data center facilities.
- Tier I facilities offer basic data center infrastructure
- Tier II facilities have some redundant infrastructure capacity
- Tier III facilities offer concurrently maintainable infrastructure
- Tier IV facilities are fault tolerant
Uptime is a measure of the time a computer system has been “up” and running as opposed to downtime.
Redundancy is a property which provides fault tolerance so that all or part of a component or system can be recovered, repaired, replaced or maintained without affecting the overall performance of the system.