AS672

AS672 (DNIC-AS-00672) is an active, minimal-footprint U.S. Department of Defense autonomous system, registered under ARIN to Headquarters, USAISC (U.S. Army Information Systems Command) and administratively managed by DISA-Columbus, currently announcing a single 155.85.161.0/24 IPv4 block with near-full global routing visibility.

ARIN RDAP's autnum top-level record shows this AS was registered on 1990-04-30 and last changed on 2011-08-02. It is a legacy DNIC (Defense Network Information Center) military allocation, not a commercial or civilian network operator — there is no distinct corporate identity, public "about" page, or published peering policy tied to AS672 itself.

Its routing footprint is small but live: one /24 (256 IPv4 addresses), zero IPv6 space, seen by 324 of 325 RIPE RIS peers. CAIDA ranks it 67,700 globally with a total AS degree of 1 (0 customers, 1 peer, 0 providers) and a singleton customer cone. The one observed neighbor, corroborated via bgp.he.net, is AS1733 (a U.S. DoD/DISA-affiliated network), consistent with AS672 being a stub peered directly into DoD's own infrastructure rather than the commercial transit ecosystem. RPKI validity could not be assessed this cycle because the source query omitted a prefix parameter.

No dedicated public website or AS672-specific peering policy exists. The nearest operator-official context is DISA's general DISN Connection Process Guide, which describes DoD external connectivity as centrally routed through CIO-approved gateways rather than open peering — a description of the parent DISN architecture, not a document written for AS672.

Operator

Headquarters, USAISC (U.S. Army Information Systems Command); administrative/abuse/technical contact DISA-Columbus (Defense Information Systems Agency) [Confirmed] — https://rdap.arin.net/registry/autnum/672

Country / RIR

US, ARIN [Confirmed] — https://rdap.arin.net/registry/autnum/672

Allocated

1990-04-30 (ARIN RDAP autnum top-level registration event); last changed 2011-08-02 [Confirmed] — https://rdap.arin.net/registry/autnum/672

Org status

active per ARIN RDAP registry status [Confirmed] — https://rdap.arin.net/registry/autnum/672

Contacts

disa.columbus.ns.mbx.arin-registrations@mail.mil; registrant address Fort Huachuca, AZ (NETC-ANC CONUS TNOSC); admin/abuse address Whitehall, OH (DISA-Columbus) [Confirmed] — https://rdap.arin.net/registry/autnum/672

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-18 in Spamhaus/NANOG/general threat-intel search coverage; two direct live-source fetches failed on tooling grounds

Network & routing

Network type

U.S. military/government network under the DoD's DISN umbrella (NIPRNet/SIPRNet/JWICS); not a commercial transit/access ISP [Likely] — https://dl.dod.cyber.mil/wp-content/uploads/connect/CPG/ConnProcGuide.html

Size

1 IPv4 prefix (155.85.161.0/24, 256 addresses); 0 IPv6 prefixes; singleton customer cone (1 ASN, 1 prefix, 256 addresses) [Confirmed] — RIPEstat routing-status; CAIDA ASRank (asn=672)

Routing/peering

seen by 324/325 RIS v4 peers, 0/321 v6 peers; CAIDA degree total 1 (0 customers, 1 peer, 0 providers); sole observed neighbor AS1733 (US DoD) [Confirmed] — RIPEstat routing-status; https://bgp.he.net/AS672

RPKI

not assessed — upstream rpki-validation call was skipped (no prefix parameter supplied) [Unknown]

Notable usage

not publicly documented at the AS672-specific level; presumed U.S. Army/DoD internal network operations [Unknown]

Related ASNs

AS1733 (sole observed BGP neighbor, US DoD-affiliated) [Confirmed via bgp.he.net corroboration] — https://bgp.he.net/AS672

Analyst note

legacy 1990 DoD/Army ASN allocation that remains actively routed today (unlike many legacy blocks that go dormant); no dedicated commercial-style operator site or peering policy because it is not a conventional ISP.