AS303

AS303 is a low-numbered legacy autonomous system number registered under ARIN to the United States Department of Defense, administered by the DoD Network Information Center (DNIC) — a function run by the Defense Information Systems Agency (DISA) out of its Columbus, Ohio facility. Registered on 1989-06-26, it is among the earliest ARIN-era ASN allocations, dating to the formative years of the public Internet. The key triage point for AS303 is that it is effectively dormant today: RIPEstat and bgp.he.net agree it announces zero IPv4 and zero IPv6 prefixes, with zero RIS peers seeing it (0/323 v4 peers, 0/321 v6 peers polled) and no observable upstreams or neighbours. It was historically routed: RIPEstat first observed it on 2000-08-18 originating IPv4 prefix 205.149.122.0/24, and last observed it on 2014-03-30 originating IPv6 prefix 2001:480:6::/48 — so it has been silent in the global DFZ for roughly a decade. RPKI posture is not assessable because there are no active originations and therefore no ROAs. No notable public abuse signal was found as of 2026-06-28 — not in Spamhaus DROP/SBL/BCL, AbuseIPDB, CleanTalk ASN blacklists, NANOG archives, or community bad-ASN lists — consistent with a clean, dormant institutional ASN held by a U.S. federal agency. (PeeringDB and one community source associate AS303 historically with the Navy Personnel Research & Development Center, disestablished in 1995; the number has since remained under DNIC/DISA control.)

Operator

United States Department of Defense (DoD), administered by DISA via the DoD Network Information Center (DNIC), Columbus, OH [Confirmed] — ARIN RDAP autnum 303, peeringdb.com/org/17705

Country / RIR

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

Allocated

1989-06-26 (ARIN RDAP autnum TOP-LEVEL registration event — NOT an IEEE date, NOT a nested entity/contact date); last changed 2025-09-12 [Confirmed] — ARIN RDAP autnum top-level events (A2, A3 agree)

Org status

active U.S. federal agency (DoD combat support agency DISA; successor to the Defense Communications Agency, 1960; DISA established 1991) [Confirmed] — en.wikipedia.org/wiki/Defense_Information_Systems_Agency

Contacts

disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil (technical/NOC); disa.columbus.ns.mbx.arin-registrations@mail.mil (registration); registrant 3990 E. Broad Street, Columbus, OH 43218 [Confirmed] — RIPEstat abuse-contact-finder, ARIN RDAP

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-28 — not in Spamhaus DROP/SBL/BCL, AbuseIPDB, CleanTalk, NANOG archives, community bad-ASN lists, or BGP hijack/route-leak records; zero-prefix state means no live attack surface under this ASN

Network & routing

Network type

U.S. federal government / military; stub/legacy ASN tied historically to the Defense Information Systems Network (DISN). Not a commercial ISP or transit provider [Confirmed/Likely] — peeringdb.com/org/17705, en.wikipedia.org/wiki/Defense_Information_System_Network

Size

dormant — 0 IPv4 prefixes / 0 IPv4 addresses and 0 IPv6 prefixes; 0 announced address space [Confirmed] — RIPEstat routing-status (2026-06-27), bgp.he.net/AS303

Routing/peering

NOT announced — 0 RIS peers seeing it (0/323 v4, 0/321 v6); 0 observed neighbours, no upstreams or peers visible; PeeringDB lists policy "Open" but with no IX facilities and no prefixes (effectively non-public / internal DoD routing)

[Confirmed] — RIPEstat routing-status, bgp.tools/as/303, peeringdb.com/asn/303

RPKI

not assessable — AS303 announces no prefixes, so there are no ROAs to validate [Confirmed] — RIPEstat rpki-validation (no --prefix; nothing to evaluate)

Historical routing

first seen 2000-08-18 (205.149.122.0/24), last seen 2014-03-30 (2001:480:6::/48); silent in the global table since [Confirmed] — RIPEstat routing-status

Notable usage

one of ~20 DoD-block ASNs managed by DNIC; held as a reserved/inactive legacy institutional assignment. Historically associated with the Navy Personnel Research & Development Center (NPRDC, disestablished 1995) per community sources [Confirmed for DoD/DNIC; Likely for the NPRDC origin] — ARIN RDAP, peeringdb.com/org/17705, A5 community angle

Related ASNs

DoD operates dozens of other active ASNs under the DNIC umbrella (e.g. AS749, AS27064, AS27065, AS27066); abuse signals on those are out of scope for AS303 [Confirmed] — bgp.tools/as/749, bgp.tools/as/303

Analyst note

Encountered as a dormant legacy DoD ASN. ARIN registration remains active, but live routing ceased ~2014; 0 prefixes, 0 peers, 0 cone today. Clean, inactive ASN. The 1989-06-26 allocated_date is the autnum top-level registration event (A3 explicitly distinguished it from nested entity dates 1993-05-26 and 2009-06-24, which are decoys).