AS461

AS461 is a legacy autonomous system number registered under ARIN within the AFCONC-BLOCK1-AS block, a range spanning AS379 through AS508 that is administratively tied to Air Force Systems Networking, a U.S. Department of Defense / U.S. Air Force network. The ARIN RDAP registrant organization on record is "7ESG" (Air Force Systems Networking), with a registered address at Maxwell AFB, Alabama, while day-to-day abuse, administrative, and technical contact routes to DISA (Defense Information Systems Agency), Columbus, Ohio. Operationally, AS461 is a small, single-homed stub network: it announces exactly one IPv4 prefix, 144.88.4.0/24 (256 addresses), no IPv6 space, has zero customers, zero settlement peers, and one upstream provider per CAIDA's AS-relationship data. Visibility is near-complete on IPv4 (seen by 324 of 325 RIPE RIS peers) and nonexistent on IPv6 (0 of 321 peers), consistent with a legacy DoD administrative block rather than a public-facing service network. CAIDA's AS Rank places it at 67,700 globally, reflecting minimal routing footprint, and flags it as a clique member — an artifact of CAIDA's Tier-1 detection heuristic rather than genuine transit-free status, since the ASN itself has a single upstream and no peers. No PeeringDB record exists for AS461 specifically (the related PeeringDB org 20118 lists a different set of ASNs). No notable public abuse or threat-feed signal was found as of 2026-07-05 after checking Spamhaus, abuse.ch, and NANOG mailing-list archives; this reflects the ASN's low public profile rather than a certified clean history.

Operator

Air Force Systems Networking (ARIN registrant org "7ESG"), U.S. Department of Defense / U.S. Air Force; registered address 501 East Moore Dr. Bldg 884 Rm 1100, Gunther Annex, Maxwell AFB, AL 36114 [Confirmed] — https://rdap.arin.net/registry/autnum/461

Country / RIR

US, ARIN [Confirmed] — https://rdap.arin.net/registry/autnum/461

Allocated

1989-08-04 (ARIN RDAP autnum top-level registration event, read from the covering block record AS379–AS508 "AFCONC-BLOCK1-AS"; this is a first-party RIR registry fact, not an IEEE/OUI-style artifact) [Confirmed] — https://rdap.arin.net/registry/autnum/461. Note: this date is inherited from the multi-ASN block delegation object rather than a standalone AS461-only registration record; last changed 2008-06-06 per the same top-level events array.

Org status

active per ARIN RDAP status field; no indication of deprecation or reassignment [Confirmed] — https://rdap.arin.net/registry/autnum/461

Contacts

disa.columbus.ns.mbx.arin-registrations@mail.mil (abuse/administrative/technical, DISA Columbus) [Confirmed] — https://rdap.arin.net/registry/entity/REGIS10-ARIN

Security/abuse context (NEUTRAL, DATED)

no notable public abuse or threat-feed signal found as of 2026-07-05 after checking Spamhaus, abuse.ch, and NANOG mailing-list archives; low public routing footprint is consistent with a low-visibility DoD-assigned block rather than a confirmed clean record [Confirmed absence-of-evidence] — https://www.spamhaus.org/resource-hub/threat-intelligence/how-to-report-suspicious-activity-to-spamhaus/, https://archive.nanog.org/list/archives.html

Network & routing

Network type

U.S. government/military administrative network; single-homed stub AS (one announced prefix, no downstream customers) [Confirmed] — https://rdap.arin.net/registry/autnum/461, https://ipinfo.io/AS461

Size

1 IPv4 prefix (144.88.4.0/24, 256 addresses), 0 IPv6 prefixes; customer cone = 1 ASN (itself), 1 prefix, 256 addresses per CAIDA [Confirmed] — https://stat.ripe.net/AS461, https://asrank.caida.org/asns/461

Routing/peering

announced and visible on IPv4 (324/325 RIS peers), not visible on IPv6 (0/321 peers); CAIDA AS degree total=1 (customer=0, peer=0, provider=1); observed_neighbours=1 per RIPEstat; no named peer/upstream ASN supplied in source data

[Confirmed] — https://stat.ripe.net/AS461, https://asrank.caida.org/asns/461

RPKI

Unknown/not evaluated — RIPEstat rpki-validation was skipped in the source pull because no specific prefix was supplied for validation [Unknown] — https://stat.ripe.net/AS461

Notable usage

administrative/internal DoD network block; first seen announcing 144.88.4.0/24 on 2022-10-19, still announcing as of 2026-07-05; no hosted public-facing domains detected [Likely] — https://stat.ripe.net/AS461

Related ASNs

part of the shared ARIN block AS379–AS508 ("AFCONC-BLOCK1-AS"); no dedicated PeeringDB record for AS461 (PeeringDB org 20118 "Air Force Systems Networking" lists a different, non-overlapping set of ASNs: AS123, AS65, AS175, AS221, AS301) [Confirmed] — https://www.peeringdb.com/org/20118

Analyst note

RDAP resolves AS461 to a shared block-registration object (AS379–AS508) rather than a standalone per-ASN delegation record; the allocated_date is recorded per instructions as the block's first-party RIR registration event, annotated as block-inherited rather than AS461-specific. No PeeringDB record and no community/NANOG corroboration exists for AS461 individually — consistent with a low-profile legacy DoD administrative ASN.