AS431

AS431 is a U.S. Department of Defense autonomous system number that resolves in ARIN's RDAP to the shared block record AFCONC-BLOCK1-AS (RDAP handle AS379), a contiguous ARIN allocation spanning AS379 through AS508 registered to "Air Force Systems Networking" (ARIN OrgId 7ESG) at 501 East Moore Dr., Bldg 884, Rm 1100, Gunther Annex, Maxwell AFB, AL. Administrative, technical, and abuse contact is handled through DISA-Columbus (disa.columbus.ns.mbx.arin-registrations@mail.mil), the Defense Information Systems Agency operations center in Whitehall, OH. This is a government/military numbering block, not a commercial ISP, hosting, content, or transit network, and it has no operator-official about, peering, or investor-relations page — consistent with roughly thirty already-researched sibling ASNs in the same block. The key triage point for AS431 is that it is effectively dormant today: RIPEstat reports announced=false with an empty announced-prefixes list and 0/324 (v4) and 0/320 (v6) RIS peers seeing it. It did originate a single /24 (192.35.109.0/24, 256 addresses) intermittently between 2026-01-25 and 2026-06-06 per RIPEstat routing-status, but nothing is in the current live announced set. CAIDA ranks it 67,700 with a singleton customer cone (1 ASN, 1 prefix, 256 addresses) and a degree of one provider, zero peers, zero customers. RPKI posture is not assessable from the ASN alone. No notable public abuse, blocklist, or BGP-hijack signal surfaced for AS431 as of 2026-07-02 — a sourced null, not proof of a clean history, and expected for a closed military network with limited public visibility.

Operator

Air Force Systems Networking (U.S. DoD / U.S. Air Force; ARIN OrgId 7ESG), administered by DISA-Columbus [Confirmed] — ARIN RDAP autnum/431 (rdap.arin.net/registry/autnum/431), registrant org 7ESG

Country / RIR

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

Allocated

1989-08-04 (ARIN registry TOP-LEVEL autnum registration event on the parent AFCONC-BLOCK1-AS block; a first-party RIR fact, NOT nulled); last changed 2008-06-06 [Confirmed] — ARIN RDAP autnum top-level events; cross-checked bgp.tools/as/431

Org status

active per ARIN RDAP status array (inherited from the parent AS379 block record); no operator-official page confirms current operational routing for AS431 specifically; third-party BGP data shows it currently dormant/unrouted [Confirmed for RDAP status; Likely for operational dormancy] — ARIN RDAP, RIPEstat

Contacts

disa.columbus.ns.mbx.arin-registrations@mail.mil (abuse/admin/tech, DISA-Columbus, +1-844-347-2457 ext2); registrant Maxwell AFB, AL [Confirmed] — ARIN RDAP REGIS10-ARIN entity, RIPEstat abuse-contact-finder

Website

none found — no operator-official public-facing page exists for AS431 / AFCONC-BLOCK1-AS / Air Force Systems Networking as a distinct entity [Confirmed] — honest sourced null (no operator IR/about/peering page located)

Security/abuse context (NEUTRAL, DATED)

no notable public abuse, blocklist, or BGP-hijack/route-leak signal found as of 2026-07-02 — nothing naming AS431 on Spamhaus ASN-DROP context, AbuseIPDB, curated bad-ASN lists, or NANOG archives; those lists target commercial VPN/hosting ASNs, a category AS431 does not fall into. Sourced null, not a clean-history confirmation

Network & routing

Network type

U.S. government/military network (DoD / USAF), DISA-administered; legacy block member, not a commercial ISP/hosting/transit network [Confirmed] — ARIN RDAP, disa.mil DISN references

Size

dormant — 0 IPv4 prefixes / 0 IPv4 addresses and 0 IPv6 prefixes currently; single historical /24 (192.35.109.0/24 = 256 addresses); customer cone = 1 ASN (itself), 1 prefix, 256 addresses [Confirmed] — RIPEstat routing-status / announced-prefixes / CAIDA AS Rank (2026-07)

Routing/peering

NOT announced — RIPEstat announced=false, 0 RIS peers seeing it (0/324 v4, 0/320 v6); CAIDA degree total 1 (customer 0, peer 0, provider 1); observed_neighbours 0 at query time [Confirmed]. No published peering policy — PeeringDB org/20118 has no policy/website and no AS431 net record (asn/431 → 404); DoD external connectivity is gated through DISN gateways, not per-ASN bilateral peering

[Confirmed] — peeringdb.com/org/20118, peeringdb.com/asn/431

Upstream

CAIDA reports exactly 1 provider but does not name the ASN in the available data; RIPEstat observed_neighbours=0 in the window (consistent with the AS being unannounced at query time) [Unknown] — asrank.caida.org/asns/431, stat.ripe.net/AS431

RPKI

not assessable — RIPEstat rpki-validation was skipped (requires a specific --prefix, which was not supplied); not independently checked [Unknown]

Notable usage

none documented on any operator-official source. AS431 is a within-block number of the historical AFCONC-BLOCK1-AS allocation (AS379–AS508) [Confirmed] — ARIN RDAP; third-party BGP registries (bgp.he.net/AS431, bgp.tools/as/431)

Related ASNs

AS379–AS508 (the AFCONC-BLOCK1-AS block; many siblings already researched, e.g. AS379, AS385, AS386) [Confirmed] — ARIN RDAP startAutnum 379 / endAutnum 508

Geo footprint

CAIDA geolocates AS431 at lon −77.34 / lat 38.96 (Washington DC area), country US; RDAP registrant address Maxwell AFB, AL; DISA POC Whitehall, OH — DoD/USAF infrastructure, not a single fixed public geo point [Confirmed] — asrank.caida.org/asns/431, ARIN RDAP

Analyst note

RDAP handle AS379 reflects the block's designated representative record, not a data error; AS431 falls inside startAutnum 379 / endAutnum 508. Entity-nested dates (REGIS10-ARIN reg 2009-06-24; 7ESG org reg 2008-06-05) are decoys — the allocated_date is the top-level autnum registration (1989-08-04). Generic "AS431" web search collides with an Alaska Airlines flight number and a Diodes Inc. part; those did not contaminate any field (all data from RIR/BGP-registry sources).