AS227

AS227 is a legacy U.S. military autonomous system number registered under ARIN to "Headquarters, USAISC" — the U.S. Army Information Systems Command, established in 1984 at Fort Huachuca, Arizona to centralize Army information management, automation, and communications, including early secure DoD backbones such as AUTODIN. The registrant entity is administratively defunct: USAISC was inactivated/realigned in 1996, with its mission ultimately passing to the U.S. Army Network Enterprise Technology Command (NETCOM, established 2002), which today operates and defends the Army's portion of the DoD Information Network from the same Fort Huachuca location. The key triage point for AS227 is that it is completely dormant in global routing. Every routing source consulted (RIPEstat, CAIDA AS Rank, bgp.he.net, bgp.tools) agrees it announces zero IPv4 and zero IPv6 prefixes, with 0 RIS peers seeing it and a customer cone of one (itself). Historically the ASN originated 141.190.0.0/16 and a few smaller blocks, was first seen in RIS around August 2000, and was last visible in the global table on 2012-04-17 before being fully withdrawn. The only ever-observed BGP peer was AS27066 (U.S. Department of Defense), a DoD-internal relationship rather than commercial transit. RPKI posture cannot be assessed because there are no active originations and therefore no ROAs. No notable public abuse signal was found as of June 2026 — not in Spamhaus ASN-DROP, NANOG archives, AbuseIPDB, or CleanTalk — consistent with a clean, dormant government/military ASN under DISA-Columbus administrative management. AS227 also appears in RFCs 2280 and 2622 purely as a routing-policy example, not as evidence of operational activity.

Operator

Headquarters, USAISC — U.S. Army Information Systems Command (ARIN org handle HEADQU-3, Fort Huachuca, AZ 85613) [Confirmed] — ARIN RDAP autnum/227, whois.arin.net/rest/asn/AS227

Country / RIR

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

Allocated

1988-10-07 (ARIN RDAP autnum top-level registration event, NOT an IEEE date — IEEE publishes no ASN registration dates); last changed 2011-08-24 [Confirmed] — ARIN RDAP autnum/227 top-level events

Org status

registrant entity is defunct/inactivated (USAISC inactivated 1996); ARIN registration remains active/allocated; successor chain ended at NETCOM (est. 2002, Fort Huachuca); technical/abuse management falls to DISA-Columbus (300 North James Road, Whitehall, OH 43213)

[Confirmed] — ARIN RDAP, en.wikipedia.org/wiki/Army_Network_Enterprise_Technology_Command

Contacts

abuse disa.columbus.ns.mbx.arin-registrations@mail.mil (DISA-Columbus, handle REGIS10-ARIN); successor org NETCOM at army.mil/Netcom [Confirmed] — ARIN RDAP, RIPEstat abuse-contact-finder, army.mil/Netcom

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-19 — not in Spamhaus ASN-DROP (direct JSON check, 227 absent), NANOG archives, AbuseIPDB, or CleanTalk; dormant government/military ASN [Confirmed for Spamhaus; Likely for AbuseIPDB/CleanTalk where direct scraping returned 403] — spamhaus.org/drop/asndrop.json, seclists.org/nanog, bgp.he.net/AS227

Network & routing

Network type

U.S. federal government / U.S. Army (DoD/DISA) military network; legacy and inactive — not a commercial ISP [Confirmed] — bgp.he.net/AS227, bgp.tools/as/227, ARIN RDAP

Size

dormant — 0 IPv4 prefixes / 0 IPv4 addresses and 0 IPv6 prefixes; customer cone = 1 ASN (itself), 0 prefixes, 0 addresses [Confirmed] — RIPEstat routing-status / announced-prefixes, CAIDA AS Rank

Routing/peering

NOT announced — 0 RIS peers seeing it (0/327 v4, 0/324 v6); CAIDA degree total 0 (customer 0, peer 0, provider 0); fully withdrawn from the global table since ~2012-04-17 [Confirmed] — RIPEstat routing-status, bgp.he.net/AS227, bgp.tools/as/227

Peering policy

none active; not present in PeeringDB (404); only ever-observed peer was AS27066 (DoD), a DoD-internal relationship, not commercial transit [Confirmed] — peeringdb.com, bgp.he.net/AS227

RPKI

not assessable — AS227 announces no prefixes, so there are no ROAs to validate; bgp.he.net shows all RPKI metrics at zero [Confirmed] — bgp.he.net/AS227

Notable usage

historically supported Army-wide information systems and communications under USAISC (1984–1996); historically originated 141.190.0.0/16 and smaller blocks (204.208.85.0/24 first-seen 2000-08-18; 204.37.170.0/24 flagged bogon); dormant in routing since 2012; appears in RFC 2280 / RFC 2622 only as a routing-policy example [Confirmed for usage/history; Likely for the exact prefix list per third-party DB] — bgp.he.net/AS227, RFC 2622, en.wikipedia.org/wiki/Army_Network_Enterprise_Technology_Command

Related ASNs

AS27066 (U.S. Department of Defense) — sole historically observed peer [Confirmed] — bgp.he.net/AS227

Analyst note

Encountered as a dormant legacy military ASN; WHOIS resolves to a long-inactivated Army command (USAISC), but the live mission is run by successor NETCOM under different infrastructure. Clean, inactive ASN. The allocated_date (1988-10-07) is the autnum TOP-LEVEL registration event — the entity-level HEADQU-3 date (1990-03-26) is a decoy and was not used.