Autonomous system detail

AS537

Not announced

Operated by DNIC-AS-00537 - Headquarters, USAISC.

Summary

// analyst note
Legacy DoD/DNIC-block ASN, administratively active at ARIN but not announced anywhere in global BGP (0 prefixes, 0 peers, 0 upstreams across RIPEstat/CAIDA/bgp.he.net/bgp.tools). No public operator website or PeeringDB record. allocated_date is the ARIN RDAP autnum top-level 'registration' event, corroborated by bgp.tools; two entity-level decoy dates (contact record 2009-06-24, org record 1990-03-26) were correctly excluded.
// security note
NEUTRAL/DATED: no notable public abuse signal found as of 2026-07-10 via web search against Spamhaus DROP, NANOG archives, and general threat-intel queries (not an authenticated/API-based check).
IPv4 prefixes
0
~0 addresses
IPv6 prefixes
0
—
Peer networks
0
0 up · 0 down
IANA block
1-1876
Assigned by ARIN
[ 01 ] — Context

About this ASN.

Updated  ·  Confidence: Medium

AS537 is a legacy Defense Network Information Center (DNIC) autonomous system number registered under ARIN to "Headquarters, USAISC" (U.S. Army Information Systems Command), with a registrant address at Fort Huachuca, Arizona. ARIN's RDAP record for the autnum shows a top-level registration event dated 1989-09-29, independently corroborated by bgp.tools ("Registered on 29 Sep 1989"), with the record last modified 2011-08-02; two other, entity-level dates buried in the RDAP object (a 2009-06-24 contact-record date and a 1990-03-26 org-record date) are decoys, not the ASN's own allocation date, and were correctly excluded. Every routing source checked — RIPEstat, CAIDA AS Rank, bgp.he.net, and bgp.tools — agrees the ASN is administratively active but currently unannounced: zero IPv4 and zero IPv6 prefixes, zero observed peers or upstreams, and a singleton customer cone (itself, no prefixes, no addresses). No public operator website or PeeringDB entry exists for AS537. The originating organization, USAISC, was inactivated in 1996; secondary sources disagree on which successor command absorbed its functions. No notable public abuse signal was found via web search as of 2026-07-10, consistent with a dormant DoD administrative ASN.

Operator
Headquarters, USAISC (U.S. Army Information Systems Command); ARIN org handle HEADQU-3; registrant address Fort Huachuca, AZ 85613, US [Confirmed] — https://rdap.arin.net/registry/autnum/537
Country / RIR
US, ARIN [Confirmed] — https://stat.ripe.net/data/abuse-contact-finder/data.json?resource=537 (authoritative_rir: arin)
Allocated
1989-09-29 — ARIN RDAP autnum top-level "registration" event, independently corroborated by bgp.tools; last modified 2011-08-02 [Confirmed] — https://rdap.arin.net/registry/autnum/537 , https://bgp.tools/as/537
Org status
registrant org USAISC was inactivated 1996-10-01; sources conflict on the successor — one (Wikipedia/CECOM) traces functions to the U.S. Army Information Systems Engineering Command under Army CECOM, HQ Fort Huachuca AZ, another (Wikipedia/Army Network Enterprise Technology Command lineage) to U.S. Army Signal Command / NETCOM. The ASN registration itself remains listed "active" at ARIN, unmodified since 2011-08-02 [Likely — conflicting secondary sources, stated as a range] — https://en.wikipedia.org/wiki/United_States_Army_Information_Systems_Engineering_Command , https://en.wikipedia.org/wiki/Army_Network_Enterprise_Technology_Command
IANA reference
left blank — no RFC/registry reference document was found for this legacy DNIC allocation [Unknown]

Abuse contact

disa.columbus.ns.mbx.arin-registrations@mail.mil (handle REGIS10-ARIN, DISA-Columbus, Whitehall, OH)

[Confirmed] — https://stat.ripe.net/data/abuse-contact-finder/data.json?resource=537

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-10 via web search against Spamhaus DROP, NANOG mailing-list archives, and general threat-intel queries; this is a web-search finding, not an authenticated/API-based clean-record certification

[Likely] — https://www.spamhaus.org/blocklists/do-not-route-or-peer/ , https://bgp.he.net/AS537

Network & routing

Network type
Government / Military (U.S. Department of Defense, U.S. Army) — inferred from the DNIC block naming and org identity, not an explicit operator self-description [Likely] — https://rdap.arin.net/registry/autnum/537
Routing status
NOT announced — 0 IPv4 and 0 IPv6 prefixes across all sources; 0/325 v4 and 0/322 v6 RIS peers seeing it; 0 observed neighbours [Confirmed] — https://stat.ripe.net/data/routing-status/data.json?resource=537 , https://bgp.he.net/AS537 , https://bgp.tools/as/537
Customer cone / AS degree
singleton cone (1 ASN, 0 prefixes, 0 addresses); AS degree total 0 (0 customer / 0 peer / 0 provider) [Confirmed] — https://api.asrank.caida.org/v2/restful/asns/537
CAIDA AS Rank
79,459; cliqueMember=false; seen=false (not observed in CAIDA's topology data) [Confirmed] — https://api.asrank.caida.org/v2/restful/asns/537
RPKI
not assessable — no announced prefixes, so RIPEstat's rpki-validation tool was skipped (requires a prefix argument) [Confirmed] — https://stat.ripe.net/data/rpki-validation/data.json?resource=537
Peering policy
Unknown / not publicly published; no PeeringDB net record found for AS537 (HTTP 404) [Unknown] — https://www.peeringdb.com/api/net?asn=537
Geo footprint
US (RDAP registrant + CAIDA country.iso); CAIDA latitude/longitude both report 0 — a placeholder, not a real coordinate [Confirmed] — https://rdap.arin.net/registry/autnum/537 , https://api.asrank.caida.org/v2/restful/asns/537
Official website
Unknown / none found [Unknown]
[ 02 ] — Announced prefixes

What this network routes.

0 prefixes total · RIPEstat data · cached, not real-time
// IPv4 prefixes0
No IPv4 prefixes announced.
// IPv6 prefixes0
No IPv6 prefixes announced.
[ 03 ] — Notable peers & upstreams

Who it talks to.

0 observed neighbours
Neighbour data unavailable from public BGP collectors.