AS746

AS746 is a dormant U.S. Air Force/DoD autonomous system, registered to Air Force Systems Networking under the ARIN block AS727–AS746 ("AFCONC-BLOCK2-AS") and administratively managed by DISA-Columbus, that has announced zero IPv4 and zero IPv6 prefixes since 2023-07-08.

The ASN's only recorded live routing activity was a single IPv4 prefix, 139.241.16.0/24, announced for roughly five weeks between 2023-06-02 and 2023-07-07; bgp.he.net separately flags that historical prefix as a bogon route. RIPEstat, CAIDA AS Rank, bgp.he.net, and bgp.tools all agree the ASN currently carries zero announced prefixes, zero RIS-visible peers, and a CAIDA customer cone of just itself (1 ASN, 0 prefixes, 0 addresses).

ARIN RDAP's top-level autnum record for AS746 carries only a "last changed" event dated 2008-06-06; no distinct top-level registration event is present, so the allocation date cannot be confirmed from that record — this was independently checked twice, including a live re-fetch. The registrant of record is Air Force Systems Networking at Maxwell AFB, Alabama; day-to-day RIR administration runs through DISA-Columbus in Whitehall, Ohio. No PeeringDB listing exists for AS746, and no public operator website could be located — the closest candidate, cyber.mil/dodnic, sits behind a CAC/PKI-gated login and was not accessed.

Operator

Air Force Systems Networking (U.S. Air Force); RIR block AS727-746 ("AFCONC-BLOCK2-AS"), registered address 501 East Moore Dr., Bldg 884 Rm 1100, Gunther Annex, Maxwell AFB, AL 36114. Day-to-day RIR administration handled by DISA-Columbus, Whitehall, OH [Confirmed] — ARIN RDAP autnum 746

Country / RIR

US, ARIN [Confirmed] — RIPEstat abuse-contact-finder, ARIN RDAP

Allocated

Unknown — RDAP top-level events[] carries only a "last changed" event (2008-06-06T10:03:45-04:00), no distinct top-level registration event; verified twice, including a live re-fetch. Nested entity-level registration dates (2008-06-05 registrant org; 2009-06-24 admin POC) are entity events, not the ASN's own allocation event, and are not used here

[Confirmed absence of a top-level date] — ARIN RDAP autnum 746

Org status

ARIN RDAP registration status "active" for the AS727-746 block, but the ASN itself is not currently routed/visible (dormant since 2023-07-08) — "active" reflects registration status, not routing status [Confirmed] — ARIN RDAP, bgp.he.net

Contacts

disa.columbus.ns.mbx.arin-registrations@mail.mil (abuse, authoritative RIR ARIN); admin/technical POC "DISA-Columbus", 300 North James Road, Whitehall, OH 43213; registrant "Air Force Systems Networking", 501 East Moore Dr., Bldg 884 Rm 1100, Gunther Annex, Maxwell AFB, AL 36114

[Confirmed] — RIPEstat abuse-contact-finder, ARIN RDAP

Security/abuse context (NEUTRAL, DATED)

no match in Spamhaus ASN-DROP (asndrop.txt/json, 418 records reviewed) as of 2026-07-27; NANOG-archive and additional threat-feed corroboration Unknown/incomplete due to exhausted search budget this cycle [Confirmed for Spamhaus check; Unknown for NANOG coverage] — spamhaus.org/drop/asndrop

Network & routing

Network type

U.S. military/DoD internal network administered via ARIN by DISA-Columbus; not a commercial ISP [Likely] — ARIN RDAP, bgp.he.net

Size

dormant — 0 IPv4/IPv6 prefixes and 0 addresses currently announced; historically 1 IPv4 prefix (139.241.16.0/24, 256 addresses) announced 2023-06-02 to 2023-07-07 only; customer cone = 1 ASN (itself), 0 prefixes, 0 addresses

[Confirmed] — RIPEstat routing-status, CAIDA AS Rank, bgp.he.net, bgp.tools (2026-07)

Routing/peering

NOT announced since 2023-07-08 — 0/329 RIS peers (v4), 0/324 (v6); CAIDA degree total 0 (customer 0, peer 0, provider 0); no current upstreams, peers, or IX presence. Only historically-observed peer: AS27064 (DoD Network Information Center), per bgp.he.net's archival peering table — treated as historical, not a live session. No PeeringDB listing (asn=746 query returned 404)

[Confirmed] — RIPEstat, CAIDA ASRank, bgp.he.net, PeeringDB API

RPKI

not assessable — no prefixes currently announced, so there is no live route/ROA pairing to validate; not re-queried against the historical prefix since it is no longer announced by this origin [Unknown] — stat.ripe.net

Notable usage

not visible in the global routing table since 2023-07-08; sole historical announcement was 139.241.16.0/24 (~5 weeks in mid-2023), which bgp.he.net's system flags as a bogon route [Confirmed] — bgp.he.net

Related ASNs

AS27064 (DoD Network Information Center; sole historical BGP peer) [Likely] — bgp.he.net

Analyst note

Dormant U.S. Air Force/DoD ASN within the AS727-746 AFCONC block, administered via ARIN by DISA-Columbus. No public operator website exists — cyber.mil/dodnic is CAC/PKI-gated and was correctly left unauthenticated. No abuse-feed hits found; the bogon flag on the historical prefix is a routing-hygiene classification, not confirmed abuse.