Autonomous system detail

AS623

Not announced

Operated by DNIC-ASBLK-00616-00665 - United States Department of Defense (DoD).

Summary

// analyst note
allocated_date (1990-04-19) and last_updated (2025-09-12) were read from the RDAP autnum object's TOP-LEVEL events[] array, correctly excluding the nested entity-level events belonging to the MIL-HSTMST-ARIN POC (1993-05-26), REGIS10-ARIN POC (2009-06-24), and USDDD registrant org (2007-01-12) records. Multiple independent angles (RDAP direct fetch, RIPEstat, CAIDA, and third-party web listings) corroborate the same 1990-04-19 registration and 2025-09-12 last-changed dates for the block.
// security note
NEUTRAL/DATED: no notable public abuse signal found as of 2026-07-17; not in Spamhaus ASN-DROP or NANOG archives; CleanTalk page inconclusive (no populated data returned).
IPv4 prefixes
0
~0 addresses
IPv6 prefixes
0
—
Peer networks
0
0 up · 0 down
IANA block
1-1876
Assigned by ARIN
[ 01 ] — Context

About this ASN.

Updated  ·  Confidence: High

AS623 is a legacy autonomous system number held within DNIC-ASBLK-00616-00665, a single ARIN registry block spanning AS616 through AS665 that is registered outright to the United States Department of Defense (DoD). There is no AS623-specific RDAP record separate from the block: ARIN's autnum object covers the full 50-ASN range under one registration, with the Defense Information Systems Agency's Columbus, Ohio facility (DISA-Columbus, 300 North James Road, Whitehall, OH 43213) serving as the administrative and technical point of contact, and the registrant of record listed as the United States Department of Defense (DoD), handle USDDD, at 3990 E. Broad Street, Columbus, OH 43218. The block's top-level RDAP registration event dates to April 19, 1990, with a last-changed timestamp of September 12, 2025. Every routing data source consulted — RIPEstat, CAIDA AS Rank, and Hurricane Electric's BGP toolkit — agrees AS623 is currently unrouted: zero announced IPv4 or IPv6 prefixes, zero RIS peers observing it out of 326 (v4) and 322 (v6) monitored peers, zero BGP neighbors, and a CAIDA customer cone limited to itself. This is consistent with AS623 being a reserved member of a large DoD-held block rather than an actively operated production network. No public abuse, hijack, or route-leak signal was found for AS623 in Spamhaus ASN-DROP, NANOG archives, or general threat-intelligence search, which is unsurprising given it originates no routes to abuse.

Operator / registrant
United States Department of Defense (DoD), handle USDDD, 3990 E. Broad Street, Columbus, OH 43218 [Confirmed] — https://rdap.arin.net/registry/autnum/623
Country / RIR
US, ARIN [Confirmed] — RIPEstat abuse-contact-finder (authoritative_rir: arin)
Allocated
1990-04-19, read from the RDAP autnum object's TOP-LEVEL registration event (sibling to handle/startAutnum/endAutnum/name), not the nested entity-level POC/org events; last changed 2025-09-12 [Confirmed] — https://rdap.arin.net/registry/autnum/623
Org status
active (ARIN RDAP status field) [Confirmed] — https://rdap.arin.net/registry/autnum/623
Website
no dedicated AS623-specific site found; parent organization's DISA/DoD web presence was not confirmed first-party within this pass [Unknown]

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-17 — not in Spamhaus ASN-DROP, NANOG/seclists archives, or general search; CleanTalk's page returned no populated data (inconclusive, not asserted as clean)

[Likely] — https://www.spamhaus.org/drop/asndrop.txt, https://cleantalk.org/blacklists/as623

Network & routing

Network type
government/military network infrastructure; DoD-owned block administered by DISA; currently unrouted [Likely] — https://www.esd.whs.mil/Portals/54/Documents/DD/issuances/dodi/801001p.pdf
Size / routing
0 announced IPv4 prefixes, 0 IPv6 prefixes; customer cone = 1 ASN (itself), 0 prefixes, 0 addresses [Confirmed] — RIPEstat announced-prefixes / CAIDA ASRank for AS623
Peering
not announced — 0/326 RIS peers seeing it (v4), 0/322 (v6); CAIDA asnDegree total/customer/peer/provider all 0; no PeeringDB record found; no public DoD peering policy document located [Confirmed for routing state; Unknown for a formal peering policy] — RIPEstat routing-status, https://bgp.he.net/AS623
RPKI
not assessable — AS623 announces no prefixes, so there are no route objects to validate against an ROA; the RIPEstat rpki-validation query was skipped upstream for lack of a prefix argument [Unknown] — RIPEstat rpki-validation (skipped)
Notable usage / analyst note
AS623 shows no BGP-visible activity across any source checked (bgp.he.net, RIPEstat, CAIDA); it functions as a reserved/held member of the large DNIC-ASBLK-00616-00665 DoD block rather than an operating production network [Confirmed] — https://bgp.he.net/AS623
ASN
AS623, part of block DNIC-ASBLK-00616-00665 (startAutnum 616, endAutnum 665) [Confirmed] — https://rdap.arin.net/registry/autnum/623
Administrative/technical POC
DISA-Columbus (Defense Information Systems Agency), 300 North James Road, Whitehall, OH 43213; abuse contact disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil, +1-844-347-2457 ext2 [Confirmed] — https://rdap.arin.net/registry/autnum/623
[ 02 ] — Announced prefixes

What this network routes.

0 prefixes total · RIPEstat data · cached, not real-time
// IPv4 prefixes0
No IPv4 prefixes announced.
// IPv6 prefixes0
No IPv6 prefixes announced.
[ 03 ] — Notable peers & upstreams

Who it talks to.

0 observed neighbours
Neighbour data unavailable from public BGP collectors.