AS324

AS324 is a legacy autonomous system number registered under ARIN to the United States Department of Defense (DoD). It does not carry its own per-ASN registration record at ARIN; instead it falls inside the DoD allocation block DNIC-ASBLK-00306-00371, which spans AS306 through AS371 and is administered through the DoD Network Information Center by DISA-Columbus (the Defense Information Systems Agency's Columbus, Ohio facility). The block's ARIN autnum record was registered on 1989-06-30 and last changed 2025-09-12, placing AS324 among the early ARPANET-era military allocations. Operationally, AS324 is a government/military stub: routing data from Hurricane Electric and bgp.tools shows a single upstream — AS306, itself a DoD ASN — and no external BGP peers, no downstream customers, and no commercial transit. It originates the legacy USAISC (U.S. Army Information Systems Command) address space 55.39.0.0/16 along with several /24 sub-prefixes and two IPv6 /40 prefixes (2608:12b:4600::/40, 2608:14a:4200::/40). Those prefixes were observed in BGP from 2026-06-14 through 2026-06-26, but RIPEstat's as-overview reported announced=false at the 2026-06-28 query time, suggesting the routes were withdrawn shortly before the snapshot. Hurricane Electric flags AS324 as "announces bogons," though the specific bogon prefixes did not render and no corroborating incident appears in NANOG archives or threat feeds. No notable public abuse signal was found as of 2026-06-28: AS324 is absent from the Spamhaus ASN-DROP list, absent from CleanTalk's top-300 spam ASNs, and unmentioned in NANOG archives — consistent with a tightly held military stub network.

Operator

United States Department of Defense (DoD) (ARIN org handle USDDD; block DNIC-ASBLK-00306-00371; administered by DISA-Columbus, Columbus, OH) [Confirmed] — ARIN RDAP autnum/324, bgp.he.net/AS324, ipinfo.io/AS324

Country / RIR

US, ARIN [Confirmed] — RIPEstat abuse-contact-finder (authoritative_rir: arin), ARIN RDAP autnum/324

Allocated

1989-06-30 (ARIN autnum top-level registration event for the containing block DNIC-ASBLK-00306-00371 — RIR first-party registry date, NOT an IEEE date); last changed 2025-09-12 [Confirmed] — ARIN RDAP autnum/324 top-level events

Org status

active U.S. federal government agency; registrant United States Department of Defense (DoD), administered by DISA, a DoD combat support agency [Confirmed] — ARIN RDAP autnum/324, en.wikipedia.org/wiki/Defense_Information_Systems_Agency

Contacts

disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil (NOC/technical/abuse); DISA-Columbus, 300 North James Road, Whitehall, OH 43213; registrant address 3990 E. Broad Street, Columbus, OH 43218 [Confirmed] — ARIN RDAP autnum/324

Website

no AS324-specific website; the DoD NIC contact domain is mail.mil and ipinfo.io records mail.mil as the associated domain; the broader DISA agency site is disa.mil [Likely] — ipinfo.io/AS324, disa.mil

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-28 — not in Spamhaus ASN-DROP, not in CleanTalk's top-300 spam ASNs, no NANOG archive mentions; HE "announces bogons" flag without corroborating incident; AbuseIPDB/ThreatFox/OTX inaccessible (bot-block/CAPTCHA) so those feeds are Unknown, not clean [Confirmed for Spamhaus/CleanTalk/NANOG; Unknown for AbuseIPDB/ThreatFox] — spamhaus.org/drop/asndrop.json, cleantalk.org/blacklists/asn, archive.nanog.org

Network & routing

Network type

government/military stub AS — DoD internal network managed by DISA; single-homed, no transit, no downstream ASes [Confirmed] — bgp.he.net/AS324, bgp.tools/as/324

Size

6 IPv4 prefixes within 55.39.0.0/16 (55.39.0.0/16, 55.39.25.0/24, 55.39.26.0/24, 55.39.27.0/24, 55.39.31.0/24, 55.39.32.0/24) ≈ 65,536 IPv4 addresses; 2 IPv6 prefixes (2608:12b:4600::/40, 2608:14a:4200::/40) [Confirmed] — bgp.he.net/AS324, RIPEstat announced-prefixes

Routing/peering

single upstream AS306 (also DoD) for both IPv4 and IPv6; no external BGP peers, no customers, no IXP presence; average AS path length ~8.18 hops [Confirmed] — bgp.he.net/AS324, bgp.tools/as/324. No published peering policy; AS324 is not listed as an individual network entry in PeeringDB under the DoD org

[Confirmed] — peeringdb.com/org/17705

RPKI

unvalidated — no valid or invalid RPKI-originated prefixes recorded; no ROAs deployed; bgp.he.net additionally flags a bogon-announcement note [Confirmed] — bgp.he.net/AS324

AS rank / customer cone

Unknown — not reported by bgp.he.net or bgp.tools for this ASN

Notable usage

originates legacy USAISC (U.S. Army Information Systems Command; inactivated 1996, mission absorbed by U.S. Army NETCOM) address space 55.39.0.0/16; part of the DoD NIC legacy ASN block managed under DISA-Columbus

[Confirmed] — bgp.he.net/AS324, ARIN RDAP autnum/324, en.wikipedia.org/wiki/Army_Network_Enterprise_Technology_Command

Related ASNs

AS306 (DoD upstream; block handle AS306, range AS306–AS371) [Confirmed] — ARIN RDAP autnum/324, bgp.he.net/AS324

Announced status

prefixes seen in BGP 2026-06-14 → 2026-06-26, but RIPEstat as-overview showed announced=false at the 2026-06-28 query (likely recently withdrawn) [Likely] — RIPEstat announced-prefixes/as-overview, bgp.he.net/AS324

Analyst note

Encountered as a DoD stub AS that resolves through its containing block DNIC-ASBLK-00306-00371 rather than a per-ASN record. The allocated_date is the block's top-level autnum registration event (1989-06-30); the entity-level dates inside entities[] (1993-05-26 contact POC, 2009-06-24 contact POC, 2007-01-12 USDDD org) are record dates for the contact/org objects, not the ASN allocation date.