AS346

AS346 is a legacy autonomous system number registered under ARIN to the United States Department of Defense, part of the DoD Network Information Center (DNIC) reserved block DNIC-ASBLK-00306-00371 spanning AS306–AS371. The RDAP autnum object for AS346 resolves to that block-level record (handle AS306) administered out of DISA-Columbus, Ohio. The BGP route description attributes the network to "Headquarters, U.S. Army Information Systems Command (USAISC)" — an Army command inactivated in September 1996 and redesignated U.S. Army Signal Command, with network-management functions ultimately migrating to NETCOM (established 2002); the ASN registration itself remains active under DoD/DISA. AS346 behaves as a stub network: during the 2026-06-14 to 2026-06-26 observation window it originated 9 IPv4 prefixes (drawn from the DoD-reserved 55.13.0.0/16 supernet) plus one IPv6 prefix (2608:18b:1800::/40), with a single observed neighbour (AS306, also a DoD block) and no transit role. At the 2026-06-28 snapshot RIPEstat routing-status showed zero actively announced space, indicating the prefixes had been withdrawn shortly before the query. There is no PeeringDB entry, no documented public peering policy, and no IRR AS-SET membership. Security posture is clean and dated: AS346 is absent from the Spamhaus ASN-DROP list, CleanTalk reports a 0.00% spam rate across its prefixes, and no NANOG-archive, threat-feed, or BGP-incident references to AS346 were found as of June 2026. The 2021 DoD BGP-announcement controversy (the AS8003/AS749/AS8008 "Global Resource Systems" pilot) did not involve AS346.

Operator

United States Department of Defense (DoD); BGP description attributes the network to Headquarters, U.S. Army Information Systems Command (USAISC) — inactivated 1996, functions transferred via U.S. Army Signal Command to NETCOM (est. 2002)

[Confirmed] — ARIN RDAP, bgp.he.net/AS346, en.wikipedia.org/wiki/Army_Network_Enterprise_Technology_Command

Country / RIR

US, ARIN [Confirmed] — RIPEstat abuse-contact-finder (authoritative_rir: arin), ipinfo.io/AS346

Allocated

1989-06-30 (ARIN RDAP autnum top-level registration event for block DNIC-ASBLK-00306-00371; first-party RIR fact, NOT an IEEE date); last changed 2025-09-12 [Confirmed] — rdap.arin.net/registry/autnum/346

Org status

active ASN registration under DoD/DISA; org handle USDDD (United States Department of Defense, 3990 E. Broad Street, Columbus, OH 43218); the BGP-description entity USAISC was inactivated September 1996

[Confirmed] — rdap.arin.net/registry/autnum/346, en.wikipedia.org/wiki/Army_Network_Enterprise_Technology_Command

Contacts

abuse/NOC disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil (ARIN handle MIL-HSTMST-ARIN); registrations disa.columbus.ns.mbx.arin-registrations@mail.mil (REGIS10-ARIN); DISA-Columbus, 300 North James Road, Whitehall, OH 43213; phone +1-844-347-2457 ext 2

[Confirmed for abuse via RIPEstat/RDAP] — rdap.arin.net/registry/autnum/346, RIPEstat abuse-contact-finder

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-28 — not in Spamhaus ASN-DROP (0.00% / 0 active IPs on CleanTalk), no URLhaus/threat-feed hits, no NANOG thread referencing AS346; the 2021 DoD BGP pilot involved AS8003/AS749/AS8008, not AS346 [Confirmed] — spamhaus.org/drop/asndrop.json, cleantalk.org/blacklists/as346, seclists.org/nanog, kentik.com/blog/the-mystery-of-as8003

Network & routing

Network type

U.S. Government / Military stub AS (single-homed, no transit); IPInfo classifies it as ISP/hosting, bgp.tools as content [Confirmed] — ipinfo.io/AS346, bgp.tools/as/346

Size

9 IPv4 prefixes + 1 IPv6 prefix during 2026-06-14→2026-06-26 (55.13.0.0/16 plus more-specifics 55.13.3.0/24, 55.13.8.0/24, 55.13.10.0/24, 55.13.15.0/24, 55.13.35.0/24, 55.13.72.0/21, 55.13.101.0/24, 55.13.216.0/22; IPv6 2608:18b:1800::/40); ~65,536 unique IPv4 addresses (the /16 supersedes the more-specifics); 0 announced at the 2026-06-28 snapshot [Confirmed counts; Likely for the de-duplicated address estimate] — RIPEstat announced-prefixes / routing-status

Routing/peering

NOT announced as of 2026-06-28 (announced_space 0 prefixes / 0 IPs); during the active window 324/326 RIS peers saw v4 and 324/324 saw v6; one observed neighbour (AS306, also DoD); first seen routing 2008-09-04 (55.13.0.0/16), last seen 2026-06-26 (IPv6 /40) [Confirmed]. No PeeringDB entry, no public peering policy, no IRR AS-SET

[Confirmed] — RIPEstat routing-status, bgp.he.net/AS346, bgp.tools/as/346

RPKI

not assessable — RIPEstat rpki-validation requires a specific prefix and none was supplied; no ROA posture determined [Unknown] — RIPEstat (rpki-validation skipped)

AS rank / customer cone

Unknown — CAIDA AS Rank API returned HTTP 502 [Unknown] — api.asrank.caida.org (unavailable)

Notable usage

routes DoD-assigned 55.13.0.0/16 space (the 55.0.0.0/8 block is DoD-reserved); BGP description labels prefixes "Headquarters, USAISC"; bgp.he.net notes AS346 announces bogons; upstream is AS306 (DoD parent block); associated mail domain mail.mil

[Confirmed] — bgp.he.net/AS346, bgp.tools/as/346, ipinfo.io/AS346, cidr-report.org

Related ASNs

AS306–AS371 (the DoD DNIC block DNIC-ASBLK-00306-00371); AS346's single observed upstream/peer is AS306 [Confirmed] — rdap.arin.net/registry/autnum/346, bgp.tools/as/346

Analyst note

Encountered as a legacy DoD DNIC-block ASN; RDAP resolves to the block record (handle AS306). The entities[0] (MIL-HSTMST-ARIN) event date 1993-05-26 is a POC-record registration, NOT the ASN allocation date — correctly ignored in favour of the autnum top-level 1989-06-30. Live RDAP fetch in A1 timed out; first-party RDAP facts confirmed independently by A2 and A3.