AS12311 — IAEA PO-Box 100 A-1400 Vienna

AS12311 announces 9 IPv4 prefixes covering 65,536 addresses and 0 IPv6 prefixes.

About this network

The network of the International Atomic Energy Agency, the United Nations body responsible for nuclear safeguards and safety, based at the Vienna International Centre.

What it's used for

• The agency's own operations. Every sampled address answers in reverse DNS as iaea.org, and the blocks are registered to IT-Department IAEA under the netname IAEA-OR-AT.

Notable

• Eight of the nine announced prefixes come out of 161.5.0.0/16, a legacy class B, and they descend in a neat binary ladder: a /17, then a /18, /19, /20, /21, /22, /23 and /24, each exactly half the size of the one before, together covering almost all of the /16.
• The ninth block is 130.0.70.0/24, registered as NEXTLAYER-CUSTOMER-NET — space taken from a Vienna provider rather than held by the agency itself.
• One observed BGP neighbour against 65,536 addresses. A large end site with a single way in.

Interesting

• The AS handle records the address as PO Box 100, A-1400 Vienna, which is the Vienna International Centre — the extraterritorial UN campus the IAEA shares with several other organisations. The agency was set up in 1957 under the "Atoms for Peace" framing, and its inspectorate is the body that actually visits nuclear facilities and reports on them.
• Every one of the sampled addresses returns the bare domain iaea.org rather than a per-host name, which is what a single wildcard PTR record produces across a whole range. Most networks this size hand out individual hostnames instead.

This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy.

Announced prefixes

• 130.0.70.0/24
• 161.5.0.0/19
• 161.5.33.0/24
• 161.5.34.0/23
• 161.5.36.0/22
• 161.5.40.0/21
• 161.5.48.0/20
• 161.5.64.0/18
• 161.5.128.0/17

Upstream networks

• AS1764 Next Layer Telekommunikationsdienstleistungs- und Beratungs GmbH

Adjacent networks

• AS1764 Next Layer Telekommunikationsdienstleistungs- und Beratungs GmbH

Routing security

• RPKI: 1 valid, 0 invalid and 1 not-found announcements; 1 ROAs.
• ASPA: none published.
• IRR: 100% of announcements registered; 2 route objects.
• Listed in as-sets: AS-NEXTLAYER, AS-NEXTLAYER-V6, AS-VIC, AS8218:AS-AT-CUSTOMERS, AS8218:AS-CUSTOMERS.