SLA (service level agreement)

An SLA (service level agreement) is a provider's quantified commitment on service quality: platform availability (99.9%), support response time, incident handling time. What distinguishes an SLA from a sales promise: written consequences — bill credits, refunds, termination rights — when the commitment is missed, and a verifiable measurement.

For a phone service, the SLA deserves a detailed read, because the devil lives there. What does uptime cover — the web platform, or also answering calls? Are credits automatic or upon written request? Do planned maintenance windows count in the calculation? An honest SLA explicitly excludes what it doesn't cover. And a well-posed figure is already information: 99.9% availability is roughly 8 hours 46 minutes of downtime per year — to weigh against what one hour without a phone costs you.