th less risk - no proxies connect to the new version until the user explicitly chooses to. This allows gradually migrating workloads to the new control plane, while monitoring changes using Istio telemetry to investigate any issues, just like using <code>VirtualService</code> for workloads. Each independent control plane is referred to as a &ldquo;revision&rdquo; and has an <code>istio.io/rev</code> label.</p><h2 id=understanding-upgrades>Understanding upgrades</h2><p>Upgrading Istio is a complicated proces