Glossary
Vendor Reliability
How consistently a third-party service meets its expected behavior over time.
Definition
Vendor reliability is the measured consistency of a third-party service - uptime, latency distribution and incident frequency - observed independently over stated windows and origin sets.
The problem
Self-reported “99.99% uptime” figures rarely state the window, the origin set, or how outcomes were classified. A number without those is marketing.
Why it matters
Reliability determines architecture (retries, fallbacks, multi-vendor), contract terms (SLA clauses, credits), and incident readiness (who gets paged).
Practical example
Two payment providers both claim four nines. Independent 30-day measurement shows one at 99.98% with a 340 ms p95 and no confirmed fault window, the other at 99.91% with three. The comparison is only meaningful because the window and the observation count are printed beside each figure.
How RELIASTRA approaches it
RELIASTRA publishes aggregates only for vendors made public, always with the window, the observation count and the observation point stated. Observatory pages show availability, latency and incident history as measured - never mirrored from a status page.
Add one dependency you already own.
RELIASTRA probes the external services your software relies on, confirms a fault deterministically, and keeps a record you can verify later. One plan, $9/month, and a 14-day trial that needs no card.