AS368

AS368 is a legacy autonomous system number registered under ARIN to the United States Department of Defense (DoD), held through the registrant handle USDDD. It is not allocated as a standalone ASN but as one number inside the block registration DNIC-ASBLK-00306-00371, which spans AS306 through AS371 — a range the ARIN autnum record dates to a top-level registration event of 1989-06-30, one of the oldest registration cohorts in the ARIN registry. Day-to-day registry contact and operation run through the Defense Information Systems Agency (DISA), specifically DISA-Columbus / the DoD Network Information Center (DoD NIC) in Whitehall and Columbus, Ohio, which hold the NOC, technical, administrative, and abuse contact roles. Unlike the dormant legacy blocks common in this range, AS368 is actively announced: as of 2026-07-01 it originates seven IPv4 prefixes (roughly 131,072 announced addresses across 55.42.0.0/16, 55.87.0.0/16 and several longer prefixes) plus one IPv6 prefix (2608:10a:4700::/40), and it is broadly visible in BGP (323/325 RIS peers for v4, 323/323 for v6, first observed routing in 2011). Third-party tooling classifies it as a stub AS, consistent with a segregated military network that consumes rather than provides transit. No named upstreams, peers, AS-rank, or customer-cone figures could be corroborated from public BGP tools within the one-fetch budget, so those remain Unknown rather than guessed. No public abuse signal, Spamhaus ASN-DROP listing, NANOG discussion, or reputation-database entry was found for AS368 as of 2026-07-01 — a clean, dated null consistent with a low-visibility U.S. government allocation.

Operator

United States Department of Defense (DoD); registrant handle USDDD [Confirmed] — ARIN RDAP autnum/368; corroborated ipinfo.io/AS368

Country / RIR

US, ARIN [Confirmed] — ARIN RDAP autnum/368; RIPEstat abuse-contact-finder (authoritative_rir: arin)

Allocated

1989-06-30 (ARIN autnum TOP-LEVEL registration event for the DNIC-ASBLK-00306-00371 block; a first-party RIR registry fact, NOT an IEEE/database artifact); last changed 2025-09-12 [Confirmed] — ARIN RDAP autnum top-level events (agreed by angles A2, A3, A5)

ASN block

DNIC-ASBLK-00306-00371 (AS368 falls within AS306–AS371, allocated as a block, not a standalone ASN) [Confirmed] — ARIN RDAP autnum/368; RIPEstat as-overview

Org status

active (per ARIN RDAP autnum status field) [Confirmed] — ARIN RDAP autnum/368

Contacts

abuse/hostmaster disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil; registrations disa.columbus.ns.mbx.arin-registrations@mail.mil; tel +1-844-347-2457; registrant address 3990 E. Broad Street, Columbus, OH 43218; DISA-Columbus admin 300 North James Road, Whitehall, OH 43213

[Confirmed] — ARIN RDAP autnum/368; RIPEstat abuse-contact-finder

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-01 — not in Spamhaus ASN-DROP, NANOG archives, or reputation databases (Talos, NERD, AbuseIPDB); low-visibility U.S. government network. Numeric search for "AS368" is noisy (unrelated flight/part numbers), so this is a dated null, not a definitive live-API clean bill

Network & routing

Network type

U.S. federal government / military network infrastructure; classified by third-party lookup as a stub AS (single-homed, no transit) [Likely] — ipinfo.io/AS368

Size / routing

announced — 7 IPv4 prefixes (~131,072 addresses: 55.42.0.0/16, 55.42.96.0/22, 55.87.0.0/16, 55.87.96.0/22, 55.87.100.0/24, 55.87.101.0/24, 55.87.255.0/24) + 1 IPv6 prefix (2608:10a:4700::/40) as of 2026-07-01 [Confirmed] — RIPEstat announced-prefixes / routing-status

Peering / upstreams

Unknown — no PeeringDB record (peeringdb.com/asn/368 and the PeeringDB API both 404); no named upstreams or peer table returned by RIPEstat; observed_neighbours=1 in routing-status but no named peer list [Unknown] — ARIN RDAP autnum/368; RIPEstat routing-status

AS rank / customer cone / RPKI

Unknown — AS-rank and customer-cone not returned; RPKI validation skipped (requires a specific prefix argument, not an ASN-level value) [Unknown]

Notable usage

associated domain mail.mil observed by third-party lookup; no operator-official AS368-specific usage documentation found [Likely] — ipinfo.io/AS368

Administrative operator

Defense Information Systems Agency (DISA), DISA-Columbus / DoD Network Information Center (DoD NIC) — holds NOC/technical/administrative/abuse RIR roles [Confirmed] — ARIN RDAP autnum/368

RIS visibility

v4 323/325 RIS peers, v6 323/323 RIS peers (2026-07-01); first seen routing 2011-07-22, last seen 2026-07-02 (55.87.0.0/16) [Confirmed] — RIPEstat routing-status

Official website

no dedicated AS368/DNIC public operator page or peering-policy page exists; DISA's general site (disa.mil) is unrelated to this specific ASN [Likely]

Analyst note

Encountered as an actively-announced ASN inside the DoD DNIC block. The 1989-06-30 allocated_date is the autnum TOP-LEVEL registration event; nested entity/org registration events (USDDD org 2007-01-12, contacts 1993-05-26 / 2009-06-24) are decoys and were correctly excluded (angle A3). Clean, active government ASN.