Uptime Institute Tier Classification
Tier I–IVBack to Glossary
Contracts & Availability
Service Level Agreement
SLA
Contractual commitment defining minimum acceptable uptime, response times, and service quality a provider must deliver.
Full Definition
A Service Level Agreement (SLA) is a formal contract defining measurable performance targets — typically uptime percentage, mean time to repair (MTTR), and latency — along with remedies if targets are missed. Data centre colocation SLAs typically guarantee 99.9 % (≤8.7 h downtime/year), 99.99 % (≤52 min/year), or 99.999 % (≤5 min/year) facility uptime.
Also Known As
service level agreementservice level
Source Reference
ISO/IEC 19086 — Cloud SLA Framework