AS338

AS338 is a U.S. Department of Defense autonomous system number registered under ARIN and managed by the DoD Network Information Center (DNIC). It is one member of the contiguous ASN block DNIC-ASBLK-00306-00371 (AS306–AS371), a range the DoD reserves for assigning to internal sub-unit networks; ARIN exposes that whole block under the single autnum record AS306, with AS338 falling inside startAutnum 306 / endAutnum 371. Day-to-day operations run out of DISA-Columbus (the Defense Information Systems Agency facility at Whitehall/Columbus, Ohio), whose hostmaster and NOC contacts appear as the technical and abuse points of contact. AS338 behaves as a stub: when active it originates four IPv4 prefixes — all inside 55.34.0.0/16 (roughly 65,536 addresses) — plus one IPv6 prefix, 2608:12a:3700::/40, and presents a single observed BGP neighbour with no downstream customers. The 55.34.0.0/16 aggregate is labeled "Headquarters, USAISC" (U.S. Army Information Systems Command) in prefix-level records, suggesting the ASN primarily carries Army command networking. Routing visibility is intermittent: RIPEstat's as-overview reported announced:false at the 2026-06-28 query time, yet announced-prefixes carried active timelines through 2026-06-26 and RIS first saw the /16 on 2008-10-30 — so the ASN was recently announcing and then withdrew or is announcing intermittently. AS338 has no RPKI ROAs (state: unknown), and bgp.he.net carries a "bogon" annotation that reflects stale filter lists predating DoD's formal re-registration of the legitimately-assigned 55.0.0.0/8 block, not an abuse signal. No public abuse, hijack, or threat-actor report was found as of 2026-06-28 — it is absent from Spamhaus ASN-DROP and has no AbuseIPDB or NANOG abuse thread.

Operator

United States Department of Defense (DoD) — DoD Network Information Center (DNIC); operated via DISA-Columbus [Confirmed] — ARIN RDAP autnum/338, ipinfo.io/AS338

Country / RIR

US, ARIN [Confirmed] — ARIN RDAP autnum/338; RIPEstat abuse-contact-finder (authoritative_rir: arin)

Allocated

1989-06-30 (ARIN registry date — autnum top-level registration event; NOT an IEEE date); last changed 2025-09-12 [Confirmed] — ARIN RDAP autnum/338 top-level events

ASN block

DNIC-ASBLK-00306-00371, range AS306–AS371; ARIN exposes the block under autnum handle AS306 (startAutnum 306, endAutnum 371) [Confirmed] — ARIN RDAP autnum/338

Org status

active U.S. federal government entity (DoD); registrant handle USDDD, 3990 E. Broad Street, Columbus, OH 43218 (DISA-Columbus) [Confirmed] — ARIN RDAP autnum/338

Website

nic.mil (DoD Network Information Center's organizational domain; no AS338-specific site); DISA portal disa.mil [Likely] — ipinfo.io/AS338, webarchive copy of nic.mil

Contacts

abuse/hostmaster disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil; +1-844-347-2457 ext. 2; DISA-Columbus, 300 North James Road, Whitehall, OH 43213 (ARIN handle MIL-HSTMST-ARIN) [Confirmed] — ARIN RDAP autnum/338

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal as of 2026-06-28 — not on Spamhaus ASN-DROP (May 2026 snapshot), no AbuseIPDB AS page (404), no NANOG abuse thread; bgp.he.net "bogon" annotation reflects stale filter lists predating DoD re-registration of the legitimate 55.0.0.0/8 block, not abuse [Confirmed for abuse-clean; Likely for the bogon rationale] — spamhaus.org/drop/asndrop.txt, bgp.he.net/AS338, en.wikipedia.org assigned-/8 blocks

Network & routing

Network type

stub AS — single-homed U.S. government/military network, no transit, zero downstreams; one observed BGP neighbour [Confirmed] — bgp.tools/as/338, bgp.he.net/AS338, RIPEstat routing-status

Size / prefixes

when active originates 4 IPv4 prefixes (55.34.0.0/16, 55.34.24.0/24, 55.34.44.0/23, 55.34.211.0/24; ~65,536 addresses) + 1 IPv6 prefix (2608:12a:3700::/40) [Confirmed] — RIPEstat announced-prefixes, bgp.he.net/AS338

Routing status

intermittent — as-overview announced:false at 2026-06-28 query time and routing-status showed 0 announced IPs, but announced-prefixes timelines ran through 2026-06-26; RIS first_seen 2008-10-30 (55.34.0.0/16), last_seen 2026-06-26 (55.34.44.0/23); visibility 324/326 v4, 324/324 v6 when active

[Confirmed] — RIPEstat as-overview / announced-prefixes / routing-status

Peering

no public peering policy; no PeeringDB entry / no IXP presence; DoD interconnection governed internally (DoDI 8010.01 / DODIN, managed by DISA), not via public policy [Likely] — bgp.tools/as/338, bgp.he.net/AS338, esd.whs.mil DoDI 8010.01

Upstream

AS306 (also U.S. DoD) cited by third-party DBs as the sole upstream; RIPEstat reports only 1 observed neighbour without naming the ASN [Likely] — bgp.he.net/AS338, ipinfo.io/AS338 (single-source for the AS306 identity)

RPKI

no ROAs present — all originations in RPKI "unknown" state (0 valid, 0 invalid); typical legacy-DoD posture [Confirmed] — bgp.he.net/AS338, bgp.tools/as/338

Notable usage

55.34.0.0/16 labeled "Headquarters, USAISC" (U.S. Army Information Systems Command) in prefix records, indicating Army command/control networking; AS338 hosts zero public domains [Confirmed] — bgp.he.net/AS338, networksdb.io headquarters-usaisc

Analyst note

Encountered as a DoD stub ASN inside the DNIC block 306–371. The RDAP record returned is the block-level handle AS306, not a per-AS record; AS338 itself lies within startAutnum/endAutnum 306–371. Allocated 1989-06-30 from the block-level autnum registration event. Lightly-peered, intermittently announcing, RPKI-unenrolled — clean, no abuse signal.