AI Dictionary › Fondamenti AI

Uptime and SLA

Uptime e SLA

Uptime is the percentage of time a service is operational and reachable; an SLA (Service Level Agreement) is the contract that fixes the promised service level, uptime included, and the compensation owed if the promise is missed. Together they turn reliability from a vague aspiration into a measurable, binding commitment.

Definition

How it works

Uptime is expressed in nines: 99.9% (three nines) allows about 8 hours 46 minutes of downtime per year, 99.99% about 53 minutes, 99.999% barely 5 minutes. Each extra nine costs exponentially more in redundancy and engineering. Alongside the SLA live SLOs (internal targets, typically stricter than the contract) and SLIs (the metrics actually measured). The error budget, the downtime still spendable, guides the balance between fast releases and stability.

Applications

In AI, SLAs are now central: LLM providers publish API availability commitments for enterprise plans, and anyone building products on those models must compose vendor SLAs with their own, planning failover and graceful degradation. Beyond AI, SLAs have governed hosting, cloud and telecommunications for decades.

History & etymology

Uptime comes from mainframe jargon, the time the machine is up, as opposed to downtime. Formal service level agreements took hold in the 1980s and 90s with IT outsourcing and telecommunications, when a contractual way was needed to define how reliable a purchased service had to be. The SLO and error budget culture was codified by Google's Site Reliability Engineering, popularized in the 2016 book of the same name.

How it's used in Grace

The Grace certification exam produces a URL that can be verified at any moment: a reliability commitment toward whoever assesses your skills, in the spirit of an SLA. In the professional scenarios on contracts and AI vendors you learn to have the AI analyze service and availability clauses.

Related terms

• Failover
• Observability
• Circuit Breaker
• Load Balancer
• Grace Certification

More in Fondamenti AI

• LLM (Large Language Model)
• Token
• Context Window
• Temperature
• AI Hallucination
• Fine-tuning
• RAG (Retrieval Augmented Generation)
• Embedding

Put it into practice

• Real scenario: apply this concept with an instant AI verdict.
• Daily gym: short drills to train dictionary concepts.
• Playoff game: challenge other players, elimination-style.

📱 Download the Android app (beta) iOS coming soon

Say what you mean. Get what you need.

Grace Certified, the AI coach that trains and certifies your prompt engineering, by Agora Intelligence.