{
  "category": "ip",
  "updated": "2026-10-08",
  "confidence_levels": {
    "verified": "Read on the official page/file.",
    "verified-archive": "Official page, read via a Wayback Machine snapshot (live site blocks automated fetches); 'archive' has the snapshot URL.",
    "secondary": "Secondary source only (e.g. Wikipedia); treat as unconfirmed.",
    "uncertain": "Plausible but not confirmed; do not rely on it."
  },
  "title": "Documentation IP address blocks",
  "note": "Never routed on the public Internet; safe in docs, examples and tests.",
  "items": [
    {
      "value": "2001:db8::/32",
      "purpose": "IPv6 documentation prefix",
      "source": "https://www.rfc-editor.org/rfc/rfc3849",
      "confidence": "verified",
      "family": "ipv6",
      "examples": [
        "2001:db8::1",
        "2001:db8:85a3::8a2e:370:7334"
      ]
    },
    {
      "value": "3fff::/20",
      "purpose": "Additional IPv6 documentation space (August 2024), for examples needing larger/multiple prefixes",
      "source": "https://www.rfc-editor.org/rfc/rfc9637",
      "confidence": "verified",
      "family": "ipv6",
      "examples": [
        "3fff::1",
        "3fff:fff:ffff::1"
      ]
    },
    {
      "value": "IANA IPv6 special-purpose registry",
      "purpose": "Authoritative list",
      "source": "https://www.iana.org/assignments/iana-ipv6-special-registry/",
      "confidence": "verified",
      "family": "ipv6"
    }
  ]
}