AS436

AS436 is a low-numbered legacy autonomous system number registered under ARIN as part of a single large block, AFCONC-BLOCK1-AS, that spans AS379 through AS508 (roughly 130 consecutive ASNs) and is held by "Air Force Systems Networking" — a U.S. Department of Defense / U.S. Air Force allocation. The ARIN registrant entity (handle 7ESG) lists an address at Maxwell AFB, Gunter Annex, Montgomery, Alabama, while the administrative, technical, and abuse contact (handle REGIS10-ARIN, a DISA-Columbus mailbox) sits at Whitehall, Ohio. The key triage point for AS436 is that it is registered but operationally dormant: every routing source consulted (RIPEstat routing-status, RIPEstat announced-prefixes, CAIDA AS Rank) agrees it announces zero IPv4 and zero IPv6 prefixes, is seen by zero of ~324 v4 / ~320 v6 RIS peers, and has zero observed neighbours. Its CAIDA AS rank of 79,459 sits near the bottom of the global ranking, its customer cone is a singleton (the ASN itself, 0 prefixes, 0 addresses), and its AS-degree is all zeros — no customers, peers, or providers. RPKI posture cannot be assessed because there are no active originations and therefore no ROAs to validate. No PeeringDB record exists, and no operator-official website, peering policy, or notable usage specific to AS436 could be found — consistent with a closed DoD/DISA connectivity model (the DISN Connection Process) rather than open commercial peering. No notable public abuse signal was found as of 2026-07-02 in Spamhaus, AbuseIPDB, abuse.ch, CleanTalk, curated bad-ASN blocklists, or NANOG archives, and no BGP hijack or route-leak incident references AS436 — consistent with a clean, dormant, legacy military ASN.

Operator

Air Force Systems Networking (U.S. DoD / U.S. Air Force block registrant, ARIN entity handle 7ESG; block AFCONC-BLOCK1-AS covers AS379–AS508); administration handled by DISA-Columbus [Confirmed] — https://rdap.arin.net/registry/autnum/436

Country / RIR

US, ARIN [Confirmed] — RIPEstat abuse-contact-finder (authoritative_rir: arin), https://rdap.arin.net/registry/autnum/436

Allocated

1989-08-04 (ARIN RDAP autnum TOP-LEVEL registration event; a first-party RIR registry date, NOT an IEEE date). Nested entity events (7ESG registrant 2008-06-05, REGIS10-ARIN contact 2009-06-24) are contact/registrant record dates, not the ASN allocation; last changed 2008-06-06

[Confirmed] — https://rdap.arin.net/registry/autnum/436

Org status

active ARIN registration (RDAP status: active) but operationally dormant/unannounced in current BGP tables; underlying block originally registered 1989-08-04, later RDAP-tracked events (2008-06-05 registrant, 2025-03-13/2026-02-12 last-changed) reflect record updates, not the original allocation

[Confirmed] — https://rdap.arin.net/registry/autnum/436

Website

Unknown / not applicable — no dedicated operator website, network portal, or peering page exists for AS436; af.mil is the general USAF public site but has no AS436-specific page [Likely] — https://www.af.mil/Web-Policy/

Contacts

abuse/admin/technical via DISA-Columbus (disa.columbus.ns.mbx.arin-registrations@mail.mil, 300 North James Road, Whitehall, OH 43213); registrant 7ESG at 501 East Moore Dr., Bldg 884 Rm 1100, Gunter Annex, Maxwell AFB, AL 36114

[Confirmed] — https://rdap.arin.net/registry/autnum/436, RIPEstat abuse-contact-finder

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-02 — not in Spamhaus (DROP/SBL), AbuseIPDB, abuse.ch, CleanTalk ASN stats, curated bad-ASN blocklists, or NANOG archives; no BGP hijack/route-leak incident references AS436; clean, dormant legacy military ASN

Network & routing

Network type

U.S. military/government network (non-commercial, non-transit); AS436 is legacy and currently unannounced/dormant, part of a ~130-ASN historical DoD block [Likely] — https://ipinfo.io/AS436, https://rdap.arin.net/registry/autnum/436

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 — 0 RIS peers seeing it (0/324 v4, 0/320 v6); CAIDA degree total 0 (customer 0, peer 0, provider 0); 0 observed neighbours; no upstreams or peers visible in any source [Confirmed] — https://stat.ripe.net/AS436, https://asrank.caida.org/asns/436

Peering policy

Unknown — no PeeringDB record exists for AS436; DoD/DISA-managed ASNs connect via the closed, request-based DISN Connection Process rather than publishing open peering policy

[Likely] — https://www.peeringdb.com/advanced_search, https://dl.dod.cyber.mil/wp-content/uploads/connect/CPG/ConnProcGuide.html

RPKI

not assessable — AS436 announces no prefixes, so there are no ROAs to validate (RIPEstat rpki-validation requires a prefix parameter) [Unknown] — https://stat.ripe.net/AS436

Notable usage

None identified specific to AS436 — 0 hosted domains, 0 announced addresses; no news coverage, incident report, or technical documentation names AS436 as distinct from the general af.mil / DoD network [Likely] — https://ipinfo.io/AS436

Community corroboration

minimal to none — no NANOG, SecLists, or Reddit (r/networking, r/ccna) discussion found, consistent with an inactive military ASN [Confirmed] — https://archive.nanog.org/list/archives.html, https://seclists.org/nanog/

Analyst note

Encountered as a dormant legacy ASN inside a large historical USAF/DoD block; WHOIS/RDAP resolve the block to Air Force Systems Networking with DISA-Columbus administration, but the ASN announces nothing and has no operator-official web presence. Clean, inactive ASN. allocated_date read strictly from the RDAP autnum top-level registration event (1989-08-04), not the nested entity decoy dates.