AS643

AS643 is a legacy autonomous system number registered under ARIN inside the DNIC-ASBLK-00616-00665 block (ASN range 616–665), delegated to the United States Department of Defense (DoD) and administered operationally by DISA-Columbus (formerly the DoD Network Information Center, or DNIC). ARIN RDAP does not return an individually named autnum record for AS643 itself — the query resolves to the shared DoD block record, whose top-level registration event dates to April 19, 1990, with the record last updated September 12, 2025. Across every routing data source consulted (RIPEstat routing-status, RIPEstat announced-prefixes, and CAIDA AS Rank), AS643 shows zero announced IPv4 and IPv6 prefixes, zero visible RIS peers out of 326 (v4) and 321 (v6) monitored peers, and a CAIDA customer cone limited to itself with zero prefixes and zero addresses — a profile consistent with a reserved-but-unannounced DoD ASN rather than an operating network. No PeeringDB record exists for AS643, and DISA's own website could not be fetched successfully to corroborate mission text beyond the ARIN registry record. No public abuse or threat-feed signal, and no NANOG or community discussion, was located for AS643 as of July 2026.

Operator / block

DNIC-ASBLK-00616-00665 — United States Department of Defense (DoD), administered by DISA-Columbus (formerly the DoD Network Information Center) [Confirmed] — https://rdap.arin.net/registry/autnum/643

Country / RIR

US, ARIN (AS643 is a DNIC sub-delegation inside the ARIN-administered block) [Confirmed] — https://rdap.arin.net/registry/autnum/643, https://stat.ripe.net/data/as-overview/data.json?resource=643

Allocated

1990-04-19 — ARIN RDAP autnum TOP-LEVEL registration event on the covering block record (handle AS616), not an entity/POC-level date (those run later: 1993, 2007, 2009); last changed 2025-09-12 [Confirmed, independently corroborated by two research passes] — https://rdap.arin.net/registry/autnum/643

Org status

Active per ARIN registry status field on the covering block record [Confirmed] — https://rdap.arin.net/registry/autnum/643

Abuse contact

disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-17 — checked Spamhaus ASN-DROP list content directly, general AbuseIPDB/CleanTalk searches, and NANOG/SecLists archive search, none AS643-specific

Network & routing

Network type

government/military — DoD address space, not a commercial ISP, transit, or content network [Likely] — https://rdap.arin.net/registry/autnum/643

Size / routing

unannounced — 0 IPv4 and 0 IPv6 prefixes; 0/326 v4 and 0/321 v6 RIS peers see it; CAIDA customer cone = singleton (1 ASN, 0 prefixes, 0 addresses); CAIDA AS rank 79459 [Confirmed] — https://stat.ripe.net/data/routing-status/data.json?resource=643, https://api.asrank.caida.org/v2/restful/asns/643

Peering

no PeeringDB record (404); no public peering policy located on disa.mil or elsewhere [Confirmed absence of a public record] — https://www.peeringdb.com/asn/643

RPKI

not assessable — RIPEstat rpki-validation requires a prefix and AS643 announces none, so there are no ROAs to check [Unknown / not applicable] — https://stat.ripe.net/data/rpki-validation/data.json?resource=643

Notable usage

Unknown/unconfirmed — a single uncorroborated web snippet named an older "PENS-NET-AS" (Navy Network Information Center) association for AS643 that could not be verified against RDAP or any official DoD/Navy page [Unknown]

Community corroboration

none found in NANOG archives, Reddit, or public incident databases — expected for low-visibility government infrastructure and not itself a red flag [Unknown, sourced-null]

Analyst note

AS643 has no individually named RDAP record; it resolves to the shared DoD block DNIC-ASBLK-00616-00665. Zero routing visibility across all sources is consistent with a reserved, non-operating DoD ASN.