AS576

AS576 (DNIC-AS-00576) is a legacy autonomous system number registered under ARIN to the United States Department of Defense (DoD), administered day-to-day by the Defense Information Systems Agency's Columbus, Ohio field office. The ARIN RDAP autnum record's top-level registration event dates the allocation to 1990-02-07, with a last-changed event of 2025-09-12 reflecting routine registry maintenance rather than reallocation. Unlike some legacy DoD ASNs that were quietly reactivated in the early 2020s to study or deter unauthorized use of dark government address space, AS576 shows no such activity: every routing source consulted (RIPEstat, CAIDA AS Rank, bgp.he.net, bgp.tools) agrees it announces zero IPv4 and zero IPv6 prefixes, has zero visible peers or upstreams, and sits near the bottom of CAIDA's global ranking (rank 79,459) with a singleton customer cone. No PeeringDB record exists for AS576 specifically, even though the DoD's PeeringDB organization page lists twenty other DoD-held ASNs. RPKI posture is not assessable given the absence of any originations. No public abuse signal was found tying AS576 to spam, hijacking, or botnet activity; a separate, unrelated 2021 press story about DoD ASN AS8003 announcing dark IPv4 space should not be conflated with this ASN.

Operator

United States Department of Defense (DoD) — registrant org handle USDDD [Confirmed] — https://rdap.arin.net/registry/autnum/576

Country / RIR

US, ARIN [Confirmed] — https://rdap.arin.net/registry/autnum/576

Allocated

1990-02-07 (ARIN RDAP autnum TOP-LEVEL "registration" event); last changed 2025-09-12 [Confirmed] — https://rdap.arin.net/registry/autnum/576

Org status

active — registrant org USDDD shows a 2025-03-13 last-changed event and RDAP autnum status "active" [Confirmed] — https://rdap.arin.net/registry/autnum/576

Contacts

two DISA-Columbus contact groups, both at 300 North James Road, Whitehall, OH 43213 — "Network DoD" (handle MIL-HSTMST-ARIN, roles noc/technical/abuse, disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil, registered 1993-05-26) and "Registration" (handle REGIS10-ARIN, roles administrative/technical, disa.columbus.ns.mbx.arin-registrations@mail.mil, registered 2009-06-24)

[Confirmed] — https://rdap.arin.net/registry/autnum/576

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-11 — not in Spamhaus ASN-DROP/blocklists, generic threat-intel queries, NANOG archives, or BGP looking-glass sources [Likely]. A distinct DoD ASN, AS8003, drew 2021 press attention for a sanctioned dark-IPv4-space BGP announcement — this is unrelated DoD-address-space history and is NOT an AS576 finding [Confirmed] — https://www.spamhaus.org/blocklists/do-not-route-or-peer/, https://www.theregister.com/2021/04/26/defense_department_ipv6/

Network & routing

Network type

U.S. federal government / military non-commercial network (DoD Network Information Center, "DNIC-AS" block); not a commercial ISP, transit provider, or IXP [Confirmed] — https://rdap.arin.net/registry/autnum/576

Size

dormant — 0 IPv4 prefixes / 0 addresses and 0 IPv6 prefixes announced; customer cone = singleton (1 ASN, 0 prefixes, 0 addresses) [Confirmed] — RIPEstat routing-status, CAIDA AS Rank (https://api.asrank.caida.org/v2/restful/asns/576), https://bgp.he.net/AS576, https://bgp.tools/as/576

Routing/peering

NOT announced — 0/325 RIS peers seeing v4, 0/322 v6; CAIDA degree total 0 (customer 0, peer 0, provider 0); no PeeringDB record for AS576 itself, though the DoD's PeeringDB org page lists 20 sibling DoD ASNs [Confirmed] — https://bgp.tools/as/576, https://www.peeringdb.com/org/17705

RPKI

not assessable — no announced prefixes exist, so there are no ROAs to validate [Confirmed] — derived from routing-status data above

Notable usage

believed part of the DoD's historic DNIC-AS-00xxx block administered by DISA-Columbus, sharing the same naming convention and contact handles seen on other DoD ASNs (e.g. AS749, AS244, AS138, AS616); not a confirmed first-party statement that AS576 itself carries specific traffic today

[Likely] — https://rdap.arin.net/registry/autnum/576, https://www.peeringdb.com/org/17705

Analyst note

Dormant legacy DoD ASN with no routing footprint in any consulted source; allocated_date is taken strictly from the ARIN RDAP autnum TOP-LEVEL registration event (1990-02-07), not from nested entity-level dates (e.g. the 1993/2007/2009 contact/org registration events, which are administrative, not allocation, facts).