AS428

AS428 is a legacy U.S. Department of Defense autonomous system number registered under ARIN to Air Force Systems Networking (ARIN OrgId handle 7ESG), with administrative, technical, and abuse roles handled by DISA-Columbus (Defense Information Systems Agency). It is one number inside the flat legacy block AFCONC-BLOCK1-AS, which ARIN records as a single autnum object spanning AS379 through AS508; ARIN's RDAP server returns that shared block record (keyed to the block-starting number 379) for any query within the range, which is expected behavior for this kind of contiguous military allocation rather than a mismatched fetch — RIPEstat's independently-keyed as-overview and abuse-contact-finder for resource 428 corroborate the same holder string and contact, so the block-level facts apply to AS428. The key triage point is that AS428 is effectively dormant: every routing source agrees it announces zero IPv4 and zero IPv6 prefixes, has zero visible BGP peers, and is not in the global routing table (RIPEstat as-overview announced: false). RIPEstat routing-status records only a brief historical origination of two /24s (199.251.166.0/24 and 199.251.165.0/24) in September–October 2001, with no announcements observed since. CAIDA AS Rank places it at #79,459 with a singleton customer cone (itself, 0 prefixes, 0 addresses) and an AS degree of zero across customer, peer, and provider. RPKI posture is not assessable because there are no active originations and therefore no ROAs to validate. No notable public abuse signal was found as of 2026-07-02 — not in Spamhaus ASN-DROP, general abuse/threat feeds, or NANOG archives — consistent with a clean, inactive number inside a large legacy DoD/USAF block. This mirrors sibling AS426's dormancy pattern; other in-block siblings (e.g. AS400) have carried a single active prefix, so dormancy is per-number, not block-wide.

Operator

Air Force Systems Networking (U.S. Air Force; ARIN registrant handle 7ESG, Maxwell AFB, AL); administered by DISA-Columbus (REGIS10-ARIN entity) [Confirmed] — ARIN RDAP autnum/428 (returns block object autnum/379)

Country / RIR

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

Allocated

1989-08-04 (ARIN RDAP top-level autnum registration event on the AFCONC-BLOCK1-AS 379–508 block — a first-party RIR fact, NOT an IEEE date); last changed 2008-06-06 [Confirmed] — ARIN RDAP autnum top-level events[]

Org status

active per ARIN RDAP status (registrant org 7ESG); third-party BGP data shows the ASN itself is currently dormant/unrouted. No operator-official (DoD/Air Force) confirmation of current operational activity [Confirmed for RDAP status; Unknown for operator-official operational confirmation] — ARIN RDAP autnum/428

Contacts

disa.columbus.ns.mbx.arin-registrations@mail.mil; DISA-Columbus, 300 North James Road, Whitehall, OH 43213; registrant address of record 501 East Moore Dr., Bldg 884 Rm 1100 Gunther Annex, Maxwell AFB, AL 36114 [Confirmed] — ARIN RDAP autnum/428, RIPEstat abuse-contact-finder

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-02 — not in Spamhaus ASN-DROP, general abuse/threat feeds (AbuseIPDB, third-party ASN blacklists), or NANOG archives; clean, inactive number in a legacy DoD block

Network & routing

Network type

U.S. government/military network (DoD / U.S. Air Force), administered by DISA; not a commercial ISP, hosting, content, or transit network. AS428 is a within-block legacy number, currently inactive [Confirmed] — ARIN RDAP autnum/428

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 / CAIDA AS Rank (2026-07)

Routing/peering

NOT announced — RIPEstat as-overview announced: false; 0 RIS peers seeing it (0/324 v4, 0/320 v6); CAIDA degree total 0 (customer 0, peer 0, provider 0); 0 observed neighbours [Confirmed]. No PeeringDB network record (net?asn=428 → 404); DoD peering is centrally gated via DISN CIO-approved gateways, not published per-ASN

[Confirmed absence] — peeringdb.com/asn/428

RPKI

not assessable — AS428 announces no prefixes, so there are no ROAs to validate (rpki-validation skipped upstream: no --prefix to check) [Confirmed]

Notable usage

none documented on any operator-official source. Historically, RIPEstat routing-status shows AS428 briefly originated 199.251.166.0/24 (first seen 2001-09-26) and 199.251.165.0/24 (last seen 2001-10-23); no announcements since [Confirmed] — RIPEstat routing-status

Related ASNs

within-block siblings of AFCONC-BLOCK1-AS (AS379–AS508), several already in this pipeline (AS379, AS385, AS386, AS389–AS391, AS393, AS397, AS398, AS400, AS426) [Confirmed] — ARIN RDAP (startAutnum 379 / endAutnum 508)

Analyst note

RDAP for AS428 resolves to the shared parent block record (handle AS379, startAutnum 379, endAutnum 508); block-level dates are attributed to AS428 because RIPEstat's per-428 holder/abuse data corroborates the same org and contact. '428 Fighter Squadron' is an unrelated USAF unit sharing the number by coincidence, excluded from findings.