AS663

AS663 is a dormant, unannounced autonomous system number that sits inside a legacy U.S. Department of Defense ASN block (DNIC-ASBLK-00616-00665, covering AS616–AS665) and has carried zero routed IPv4 or IPv6 prefixes since at least June 2025. It is not an independently delegated ASN in ARIN's records — the RDAP lookup resolves to the parent block's handle, AS616 — but it is a real, individually numbered resource within that block.

The registrant is the United States Department of Defense, with day-to-day registry administration handled by DISA-Columbus (Defense Information Systems Agency). This is a non-commercial government numbering resource, not a commercial ISP, transit provider, or content network, and it has no dedicated public-facing operator website; the historical nic.mil site is defunct and survives only as a 2008 web-archive snapshot.

ARIN's autnum record shows a top-level registration event dated 1990-04-19 for the block, with a last-changed date of 2025-09-12. Two independent research angles (operator-official lookup and routing/registry lookup) both read this date directly from ARIN RDAP's top-level events array, so it is recorded here as the allocated_date rather than nulled.

Routing data is unanimous across RIPEstat, CAIDA AS Rank, and RDAP: zero announced prefixes (IPv4 and IPv6), zero RIS peers seeing the ASN out of 325/320 total, zero CAIDA graph degree, and a customer cone limited to the ASN itself. CAIDA ranks it 79,459th globally, near the bottom of routed activity, consistent with a reserved-but-unused block member rather than a live network.

Operator

United States Department of Defense (DoD), administered by DISA-Columbus; registrant of block DNIC-ASBLK-00616-00665 [Confirmed] — https://rdap.arin.net/registry/autnum/663

Country / RIR

US, ARIN [Confirmed] — https://stat.ripe.net/data/abuse-contact-finder/data.json?resource=663 (authoritative_rir: arin)

Allocated

1990-04-19 (ARIN autnum top-level registration event, first-party RIR fact); last changed 2025-09-12 [Confirmed, two-angle corroboration] — https://rdap.arin.net/registry/autnum/663

Org status

Active per ARIN RDAP (block record, last changed 2025-09-12); AS663 itself is individually unrouted/dormant [Confirmed] — https://rdap.arin.net/registry/autnum/663

Website

Unknown/None — no dedicated operator site for AS663; nic.mil is defunct (archived only) [Confirmed null] — https://webarchive.library.unt.edu/eot2008/20080916004157/http:/nic.mil/

Security/abuse context (NEUTRAL, DATED)

not present on Spamhaus ASN-DROP as of 2026-07-17; no NANOG/seclists.org abuse or hijack threads found [Likely — absence-of-evidence, not a clean-bill guarantee] — https://www.spamhaus.org/drop/asndrop.json

Network & routing

Network type

U.S. government/military numbering resource; non-commercial, not run as an ISP or transit network [Confirmed] — https://rdap.arin.net/registry/autnum/663

Size

dormant — 0 IPv4 prefixes/addresses, 0 IPv6 prefixes; customer cone = 1 ASN (itself), 0 prefixes, 0 addresses [Confirmed] — https://stat.ripe.net/AS663, https://asrank.caida.org/asns/663

Routing/peering

NOT announced — 0/325 RIS v4 peers, 0/320 RIS v6 peers, 0 CAIDA degree (customer/peer/provider all 0); no PeeringDB listing [Confirmed] — https://stat.ripe.net/AS663, https://www.peeringdb.com/asn/663

RPKI

not assessable — no announced prefixes, so no ROAs exist to validate [Confirmed] — https://stat.ripe.net/AS663

Notable usage

legacy member of the DoD's DNIC 616-665 ASN block, historically used for internal DoD/military network segments; not visible in the global routing table since 2025-06-30 [Confirmed] — https://bgp.he.net/AS663

Related ASNs

AS616 (block record handle returned by RDAP); AS668 (adjacent in-range ASN, independently confirmed as U.S. DoD on bgp.he.net) [Confirmed for AS616; Likely for AS668 as corroboration] — https://bgp.he.net/AS668

Analyst note

Individually-delegated RDAP record does not exist for AS663; all data derives from the parent DNIC-ASBLK-00616-00665 block record. Treat as a dormant, non-commercial government ASN with no live routing or public peering footprint.