AS327

AS327 is a legacy autonomous system number registered under ARIN to the United States Department of Defense (DoD), administered by the Defense Information Systems Agency (DISA) through the DoD Network Information Center (DNIC). It is not a standalone registration but a member of the contiguous ASN block DNIC-ASBLK-00306-00371 (AS306 through AS371), whose ARIN RDAP autnum record carries a top-level registration event date of 1989-06-30 — the authoritative allocation date for the block, and therefore for AS327. The ARIN registrant handle is USDDD, with the org address listed at 3990 E. Broad Street, Columbus, OH 43218, and the administrative/technical contact at DISA-Columbus, 300 North James Road, Whitehall, OH 43213. AS327 is a stub (single-homed) AS that provides no transit and is upstream-connected to AS306, also a DoD/DNIC ASN; bgp.tools classifies it as Content. It announces the IPv4 prefix 55.45.0.0/16 (65,536 addresses) plus two more-specific /24s (55.45.119.0/24, 55.45.128.0/24) and one IPv6 prefix, 2608:14b:5100::/40, all labelled in bgp.he.net as "Headquarters, USAISC" — a reference to the former U.S. Army Information Systems Command, reorganized into NETCOM in 2002. AS327 is not currently announcing: RIPEstat shows announced=false as of the 2026-06-28 query, and all four prefixes (55.45.0.0/16, 55.45.119.0/24, 55.45.128.0/24, 2608:14b:5100::/40) carry route timelines ending 2026-06-26T16:00:00, indicating the ASN withdrew all routes around June 26, 2026 — the same coordinated timestamp as block-siblings AS326, AS328, AS329, and AS330. RIS first observed it routing on 2011-09-14, last seen 2026-06-26. No notable public abuse signal was found as of 2026-06-28: AS327 is absent from Spamhaus ASN-DROP, shows a 0.00% CleanTalk spam rate, and appears in no NANOG, BGP-hijack, or threat-intelligence archive — consistent with a tightly controlled, closed military network.

Operator

United States Department of Defense (DoD), administered by DISA / DoD Network Information Center (DNIC); ARIN registrant handle USDDD, org address 3990 E. Broad Street, Columbus, OH 43218 [Confirmed] — ARIN RDAP autnum/327

Country / RIR

US, ARIN [Confirmed] — ARIN RDAP autnum/327; RIPEstat abuse-contact-finder (authoritative_rir: arin)

Allocated

1989-06-30 (ARIN RDAP autnum top-level registration event for block DNIC-ASBLK-00306-00371; this is a first-party RIR fact, NOT an IEEE date); last changed 2025-09-12 [Confirmed] — ARIN RDAP autnum/327 top-level events

Org status

active U.S. federal government agency (Department of Defense); administrative/technical contact DISA-Columbus, 300 North James Road, Whitehall, OH 43213 [Confirmed] — ARIN RDAP autnum/327

Contacts

abuse/hostmaster disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil; DISA public site https://www.disa.mil/ [Confirmed] — ARIN RDAP autnum/327, RIPEstat abuse-contact-finder resource=327

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-06-28 — absent from Spamhaus ASN-DROP, 0.00% CleanTalk spam rate (0 of 8 detected IPs spam-active), no NANOG/BGP-hijack/threat-intel mentions

Network & routing

Network type

government / U.S. military; stub (single-homed) AS providing no transit; classified "Content" by bgp.tools; closed DoD internal network [Confirmed] — ipinfo.io/AS327, bgp.tools/as/327

Size / prefixes

55.45.0.0/16 (USAISC, ~65,536 IPv4 addresses) plus 55.45.119.0/24 and 55.45.128.0/24; IPv6 2608:14b:5100::/40 [Confirmed] — bgp.he.net/AS327, RIPEstat announced-prefixes resource=327

Routing/peering

single observed upstream/peer AS306 (also DoD); no public peering policy, no PeeringDB entry, no IXP membership; DoD connectivity governed by the DISN Connection Process Guide, not open commercial peering [Confirmed for AS306 upstream + no-PeeringDB; Likely for governance doc] — bgp.he.net/AS327, bgp.tools/as/327

Routing status

NOT currently announcing — announced=false as of 2026-06-28; all four prefixes (55.45.0.0/16, 55.45.119.0/24, 55.45.128.0/24, 2608:14b:5100::/40) withdrawn 2026-06-26T16:00:00. RIS first observed routing 2011-09-14; last seen 2026-06-26

[Confirmed] — RIPEstat routing-status / as-overview / announced-prefixes resource=327

RPKI

no valid or invalid ROAs recorded at bgp.he.net; bgp.he.net also flags bogon announcements; RIPEstat RPKI validation skipped (no prefix supplied) [Likely] — bgp.he.net/AS327

Notable usage

BGP prefix labels read "Headquarters, USAISC" — the former U.S. Army Information Systems Command (reorganized into U.S. Army NETCOM in 2002); recent internet scans show zero ICMP responders, consistent with a closed/firewalled military network [Confirmed] — bgp.he.net/AS327, ipinfo.io/AS327

Related ASNs

AS306 (DoD/DNIC, the single observed upstream and block start ASN); the block spans AS306–AS371 [Confirmed] — ARIN RDAP autnum/327, bgp.he.net/AS327

Block name

DNIC-ASBLK-00306-00371 (AS306–AS371); AS327 falls within this DoD/DNIC block [Confirmed] — ARIN RDAP autnum/327; networksdb.io/autonomous-system/AS327

Analyst note

The block-level autnum events[] date 1989-06-30 is the authoritative allocation date; the entity-level dates (USDDD registrant 2007-01-12, MIL-HSTMST-ARIN 1993-05-26, REGIS10-ARIN 2009-06-24) are org/contact record timestamps and are NOT the ASN allocation date. CAIDA AS-rank/customer-cone unavailable (API HTTP 502). AS327 is currently dormant in routing (announced=false as of 2026-06-28; all prefix timelines end 2026-06-26T16:00:00).