AS743

AS743 is a U.S. Air Force/Department of Defense autonomous system, registered under ARIN inside the AFCONC-BLOCK2-AS block (AS727–AS746) and administered through DISA-Columbus, that is currently unannounced in global BGP — zero visible IPv4/IPv6 prefixes, zero RIS peers, and a singleton customer cone.

The block's registrant org is "Air Force Systems Networking" (ARIN handle 7ESG), with registration/abuse/technical contacts routed through DISA-Columbus (Defense Information Systems Agency) in Whitehall, OH, and a registrant address at Maxwell AFB, AL. No independent public-facing operator website, peering-policy page, or PeeringDB network object exists for AS743 specifically — expected for an internal DoD network rather than a commercial operator.

RIPEstat's routing-status history shows one brief origination: the prefix 200.39.24.0/22 with first-seen and last-seen both dated 2026-05-21, a same-day appearance. Outside that event AS743 shows 0 of ~329 RIS v4 peers and 0 of ~324 RIS v6 peers observing it, 0 announced prefixes/addresses, and 0 observed neighbours. CAIDA ASRank corroborates: rank 79,459, "seen": false, zero AS-degree (customer/peer/provider all 0), and a customer cone of just the ASN itself with 0 prefixes and 0 addresses.

The autnum record's TOP-LEVEL RDAP events array carries only one entry — an eventAction of "last changed" dated 2008-06-06 — with no "registration" eventAction present. A separate 2008-06-05 date exists only at the entity level (the 7ESG registrant-org record, not the autnum top level), so per the registration-date rule that date is a decoy and is not used as allocated_date; the top-level events array genuinely carries no registration event, so allocated_date is recorded as Unknown rather than invented.

Exposure

No active BGP announcements today; the sole attack surface signal is the brief, unexplained 200.39.24.0/22 origination on 2026-05-21, which is worth flagging but not evidence of compromise on its own.

Abuse signal

Inconclusive, not a clean bill of health — Spamhaus's check tool returned HTTP 403 (blocked), bgpview.io failed DNS resolution, and the WebSearch budget was exhausted before a NANOG-archive abuse search could complete.

RPKI

Not assessable — RIPEstat's RPKI-validation tool requires a specific announced prefix, and AS743 currently announces none.

Peering policy

Unknown for AS743 itself — no PeeringDB network object exists; sibling ASNs under the same PeeringDB org (65, 123, 175, 221, 301) list "Open," but that cannot be attributed to AS743 without its own record.

Operator

Air Force Systems Networking (U.S. Air Force / DoD network; ARIN org handle 7ESG; contacts routed through DISA-Columbus) [Confirmed] — ARIN RDAP autnum/entity records

Country / RIR

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

Allocated

Unknown — the autnum's TOP-LEVEL RDAP events[] array holds only a "last changed" event (2008-06-06), no "registration" event; a 2008-06-05 date exists solely at the entity (registrant-org) level and is excluded as a decoy per the top-level-only rule [Confirmed absence of a top-level registration event] — rdap.arin.net/registry/autnum/727

Org status

active (ARIN RDAP status for the AS727–AS746 block) [Confirmed] — rdap.arin.net/registry/autnum/743

Contacts

disa.columbus.ns.mbx.arin-registrations@mail.mil (REGIS10-ARIN, DISA-Columbus, 300 North James Road, Whitehall, OH 43213); registrant org address 501 East Moore Dr., Bldg 884 Rm 1100, Gunther Annex, Maxwell AFB, AL 36114 [Confirmed] — ARIN RDAP

Security/abuse context (NEUTRAL, INCONCLUSIVE)

no abuse signal confirmed as of 2026-07-27, but Spamhaus check.spamhaus.org returned HTTP 403 and bgpview.io failed DNS resolution, so absence of evidence is not confirmed absence of abuse

Network & routing

Network type

U.S. military/government network (Air Force, administered with DISA); not a commercial or enterprise network [Confirmed] — ARIN RDAP

Size

currently unannounced — 0 IPv4/IPv6 prefixes and addresses; customer cone = 1 ASN (itself), 0 prefixes, 0 addresses; briefly originated 200.39.24.0/22 around 2026-05-21 [Confirmed] — RIPEstat routing-status/announced-prefixes, CAIDA AS Rank (2026-07)

Routing/peering

NOT currently announced — 0/329 RIS v4 peers, 0/324 RIS v6 peers; CAIDA AS-degree total 0 (customer 0, peer 0, provider 0); no PeeringDB network object for AS743 [Confirmed]. A bgp.he.net scrape claiming one BGP peer (AS7438) and Mexico-based prefixes conflicts with ARIN/RIPEstat/CAIDA and is treated as an unreliable third-party artifact [Unknown/discounted]

RPKI

not assessable — no currently announced prefixes to validate a ROA against; RIPEstat's RPKI-validation tool requires a specific prefix [Unknown] — stat.ripe.net

Notable usage

sits inside the AFCONC-BLOCK2-AS block (AS727–AS746) held by Air Force Systems Networking; briefly originated one /22 around 2026-05-21 but is otherwise dormant with no public operator site [Confirmed] — ARIN RDAP, RIPEstat

Related ASNs

AS727 (AFCONC-BLOCK2-AS block designation, spans AS727–AS746) [Confirmed]; AS65, AS123, AS175, AS221, AS301 (siblings under the same PeeringDB org 20118, "Air Force Systems Networking") [Likely]

Analyst note

Encountered as a dormant DoD/Air Force ASN inside a DISA-administered ARIN block; the ARIN autnum's top-level events carry no registration date (only a 2008-06-06 "last changed" event), so allocated_date is honestly recorded as Unknown rather than borrowing the entity-level 2008-06-05 date. The single-day 200.39.24.0/22 announcement on 2026-05-21 is the only routing activity found and is not further explained by any source consulted.