AS311

AS311 is a legacy autonomous system number registered under ARIN to the United States Department of Defense (DoD), administered by the Defense Information Systems Agency (DISA) through its DoD Network Information Center (DNIC) in Columbus, Ohio. It does not stand alone in the registry: ARIN models AS311 as a member of the contiguous block DNIC-ASBLK-00306-00371 (AS306–AS371), a range of sixty-six ASNs reserved for DoD use and held under the org handle USDDD. The triage point for AS311 is that it is dormant. Every routing source consulted — RIPEstat routing-status, bgp.tools, bgp.he.net, and Qrator Radar — agrees the ASN announces zero IPv4 and zero IPv6 prefixes, has no visible upstreams, and is absent from the global routing table. RIPEstat shows 0 of 323 RIS peers seeing any route as of 2026-06-27. The only historical footprint is a single prefix, 214.27.133.0/24, first seen in November 2013 and last seen on 2023-04-20; that block sits in DoD-reserved (bogon) space rather than the public Internet. CAIDA AS Rank data was unavailable (the endpoint timed out), so customer-cone and rank metrics stay Unknown. No notable public abuse signal was found as of 2026-06-28 — Qrator Radar reports zero route leaks, hijacks, bogons, and amplifiers, and no public blocklist, NANOG thread, or threat-intel feed returned a listing for this ASN, consistent with a clean, dormant federal allocation.

Operator

United States Department of Defense (DoD), administered by DISA via the DoD Network Information Center (DNIC); ARIN org handle USDDD [Confirmed] — ARIN RDAP autnum/311, ipinfo.io/AS311

Country / RIR

US, ARIN [Confirmed] — RIPEstat abuse-contact-finder (authoritative_rir: arin), ARIN RDAP

Allocated

1989-06-30 (ARIN registry date — first-party RIR autnum top-level registration event for the block, NOT an IEEE date); last changed 2025-09-12 [Confirmed] — ARIN RDAP autnum/311 top-level events

Org status

active allocation to a U.S. federal combat-support agency (DISA); registrant org handle USDDD; DNIC operations at Columbus, OH (3990 E. Broad Street / 300 North James Road) [Confirmed] — ARIN RDAP, en.wikipedia.org/wiki/Defense_Information_Systems_Agency

Contacts

abuse/hostmaster disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil; phone +1-844-347-2457; ARIN POC handle MIL-HSTMST-ARIN (Network DoD, DISA-Columbus) [Confirmed] — ARIN RDAP, RIPEstat abuse-contact-finder

Website

https://www.disa.mil (DISA, the administering agency; no operator site exists for AS311 specifically) [Likely] — disa.mil

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-28 — Qrator Radar reports 0 route leaks, 0 hijacks, 0 bogons, 0 amplifiers; no Spamhaus DROP/ASN-DROP, NANOG, or threat-intel listing found (some authenticated feeds — Spamhaus, Talos — returned 403 and could not be fully inspected). With 0 announced IPs there is no IP-level abuse surface

Network & routing

Network type

U.S. federal government / military network infrastructure; AS311 is allocated but dormant (no active routing) [Confirmed] — ARIN RDAP, networksdb.io (DoD NIC)

Size

dormant — 0 IPv4 prefixes / 0 IPv4 addresses and 0 IPv6 prefixes currently announced; historically 1 prefix (214.27.133.0/24, /24 = 256 addresses, DoD-reserved bogon space, last seen 2023-04-20) [Confirmed] — RIPEstat routing-status, bgp.he.net/AS311

Routing/peering

NOT announced — 0/323 v4 and 0/321 v6 RIS peers seeing it; no upstreams visible; no public peering policy published for AS311 [Confirmed]. AS311 is not in PeeringDB DoD org (org/17705); one DoD-affiliated peer (AS6045) observed historically per bgp.he.net [Likely]

RPKI

not assessable — AS311 announces no prefixes, so there are no ROAs to validate; no RPKI-valid or RPKI-invalid routes detected [Confirmed] — bgp.he.net/AS311

AS rank / customer cone

Unknown — CAIDA AS Rank endpoint timed out; no rank or cone data available [Unknown] — (CAIDA aborted on timeout)

Notable usage

AS311 is one ASN within the DoD block AS306–AS371 used for military and government network infrastructure under DISA management; AS311 itself currently routes nothing [Confirmed] — ip2location.com/as311, bgp.tools/as/311

Related ASNs

AS306–AS371 (the full DNIC-ASBLK-00306-00371 DoD block) [Confirmed] — ARIN RDAP autnum/311

Block / name

DNIC-ASBLK-00306-00371 (AS306–AS371, contiguous DoD block); startAutnum 306, endAutnum 371 [Confirmed] — ARIN RDAP autnum/311

Analyst note

Encountered as a dormant member of a contiguous DoD ASN block. WHOIS for AS311 resolves to the block record beginning at AS306; live routing is effectively nil. Clean, inactive federal ASN.