AS644

AS644 is a legacy autonomous system number registered under ARIN within the DNIC-ASBLK-00616-00665 block (AS616–AS665), assigned to the United States Department of Defense and administered operationally by the Defense Information Systems Agency (DISA) Columbus. The block-level ARIN RDAP autnum record carries a top-level registration event dated 1990-04-19 — the earliest first-party registry fact available for any ASN inside this DNIC range, since ARIN does not expose a per-ASN-unique registration date within a shared DNIC block — and a last-changed event of 2025-09-12. As of 2026-07-17, AS644 is allocated but entirely unrouted: RIPEstat's routing-status and announced-prefixes endpoints report zero IPv4 and zero IPv6 prefixes originated, zero of 326 IPv4 RIS peers and zero of 321 IPv6 RIS peers observing it, and zero BGP neighbours. CAIDA AS Rank corroborates this with rank 79,459 (near the bottom of the global ranking), seen=false, cliqueMember=false, and a customer cone containing only the ASN itself (0 prefixes, 0 addresses). No standalone PeeringDB record exists for AS644, and it does not appear among the 20 ASNs listed under the DoD's PeeringDB org record (org/17705). No public abuse or blocklist signal was found for AS644 across Spamhaus, AbuseIPDB (search-only — the direct ASN-check page returned HTTP 403 to automated fetch and could not be independently verified), or NANOG mailing-list archives, though the ASN's unrouted status structurally limits what abuse telemetry could exist in the first place. RPKI validation does not apply since no prefixes are announced.

Operator

United States Department of Defense (DoD), org handle USDDD, administered by DISA Columbus [Confirmed] — https://rdap.arin.net/registry/autnum/644

Country / RIR

US, ARIN [Confirmed] — https://rdap.arin.net/registry/autnum/644

Allocated

1990-04-19 — block-level top-level autnum registration event (no per-ASN-unique date exists within this DNIC block; first-party RIR fact, not an IEEE/database-artifact date) [Confirmed, corroborated by two angles] — https://rdap.arin.net/registry/autnum/644

Website

Unknown — DISA's public site could not be verified live via automated fetch (root and /about both resolved to an unrelated portal page) [Unknown]

IANA reference

none applicable; left blank rather than fabricated [Confirmed — blank]

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 in Spamhaus or NANOG archives; AbuseIPDB's direct ASN-check page returned HTTP 403 to automated fetch and was not independently verified, so this is a dated null result, not an assertion of cleanliness

Network & routing

Network type

government/DoD; legacy DNIC block; currently unrouted [Confirmed] — https://rdap.arin.net/registry/autnum/644

Routing/size

0 IPv4 prefixes, 0 IPv4 addresses, 0 IPv6 prefixes announced; 0/326 IPv4 RIS peers and 0/321 IPv6 RIS peers seeing it; 0 observed neighbours [Confirmed] — https://stat.ripe.net (routing-status, announced-prefixes for resource 644)

CAIDA AS Rank

79459; seen=false; cliqueMember=false; customer cone = 1 ASN (itself), 0 prefixes, 0 addresses; asnDegree total/customer/peer/provider all 0 [Confirmed] — https://api.asrank.caida.org/v2/restful/asns/644

Peering

no standalone PeeringDB record for AS644 (peeringdb.com/asn/644 returns 404); not among the 20 ASNs listed under the DoD's PeeringDB org record (org/17705) [Confirmed] — https://www.peeringdb.com/org/17705

RPKI

not assessable — no announced prefixes, so there are no ROAs to validate [Unknown / not applicable] — RIPEstat rpki-validation (skipped, no prefix supplied)

ASN / block

AS644, within DNIC-ASBLK-00616-00665 (startAutnum 616, endAutnum 665) [Confirmed] — https://rdap.arin.net/registry/autnum/644

Last changed

2025-09-12 [Confirmed] — https://rdap.arin.net/registry/autnum/644

Org / allocation status

active [Confirmed] — https://rdap.arin.net/registry/autnum/644