AS726

AS726 is an unrouted autonomous system number inside the DNIC-ASBLK-00721-00726 block, registered under ARIN to the United States Department of Defense and administered through the DoD Network Information Center (DNIC); as of 2026-07-25 it announces zero IPv4 and zero IPv6 prefixes and carries no visible BGP activity.

The registrant is the DoD itself (ARIN handle USDDD), with day-to-day registration and NOC contact handled by DISA-Columbus. No dedicated public website or peering page exists for AS726 specifically; DISA's general public site covers DoD network-connection services broadly but does not identify this ASN.

Routing data from RIPEstat, CAIDA AS Rank, and bgp.he.net agree the ASN is fully dormant: 0 announced prefixes in either address family, 0 observed peers, 0 upstreams, and a singleton customer cone (itself, 0 prefixes, 0 addresses). No PeeringDB net object exists for AS726 — a 404 on direct API query — and it is absent from the DoD org's 20-network PeeringDB listing even though several sibling DoD ASNs (AS749, AS138, AS244, AS616, AS27081) do have entries. RPKI cannot be evaluated because there are no announced prefixes to validate.

The allocation date is a genuine registry gap rather than an omission on our part: the autnum object's top-level events[] carries only a "last changed" timestamp (2025-09-12), with no registration eventAction. Several entity-level dates surface in related RDAP records (1993-05-26, 2009-06-24, 2007-01-12) and in third-party mirrors (including a 1970-01-01 epoch artifact on ipinfo.io), but none of these are the autnum's own top-level registration event, so allocated_date is recorded as Unknown rather than guessed.

Operator

United States Department of Defense (DoD); ARIN handle USDDD; block DNIC-ASBLK-00721-00726 administered by the DoD Network Information Center, operated by DISA-Columbus [Confirmed] — https://rdap.arin.net/registry/autnum/726

Country / RIR

US, ARIN [Confirmed] — https://rdap.arin.net/registry/autnum/726

Allocated

Unknown — autnum top-level events[] contains no registration eventAction, only "last changed" 2025-09-12; verified via live re-fetch to rule out truncation. Entity-level dates (1993-05-26, 2009-06-24, 2007-01-12) and a 1970-01-01 ipinfo.io epoch artifact are decoys, excluded

[Confirmed] — https://rdap.arin.net/registry/autnum/726, https://ipinfo.io/AS726

Org status

Active per ARIN RDAP; org address 3990 E. Broad Street, Columbus, OH 43218; operational NOC/abuse/registration contacts route through DISA-Columbus, 300 North James Road, Whitehall, OH 43213 [Confirmed] — https://rdap.arin.net/registry/autnum/726

Contacts

disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil; disa.columbus.ns.mbx.arin-registrations@mail.mil; +1-844-347-2457 ext2; org address 3990 E. Broad Street, Columbus, OH 43218 [Confirmed] — https://rdap.arin.net/registry/autnum/726

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-25 — not in NANOG mailing-list archives searched for AS726-specific hijack/leak/spam/abuse threads; no published abuse contact specific to this ASN. A DoD-owned prefix (205.19.72.0/23, not AS726-specific) was hijacked by AS34109/Cyberbunker in March 2013

Network & routing

Network type

U.S. federal government / military network infrastructure block (DoD/DNIC ASN allocation), not a commercial ISP or transit provider [Confirmed] — https://rdap.arin.net/registry/autnum/726

Size

dormant/unrouted — 0 IPv4 and 0 IPv6 announced prefixes, address estimate 0; CAIDA AS rank 79,459; customer cone = singleton (1 ASN, 0 prefixes, 0 addresses) [Confirmed] — https://stat.ripe.net/AS726, https://api.asrank.caida.org/v2/restful/asns/726

Routing/peering

not announced — 0 peers (v4/v6), 0 upstreams, no PeeringDB net object (404 on direct query); AS726 absent from the DoD org's 20-network PeeringDB listing though sibling DoD ASNs (AS749, AS138, AS244, AS616, AS27081) have entries; peering policy Unknown

[Confirmed] — https://www.peeringdb.com/org/17705, https://bgp.he.net/AS726, https://bgp.tools/as/726

RPKI

not assessable — no announced prefixes, so no ROAs exist to validate [Confirmed] — https://stat.ripe.net/AS726

Notable usage

no live BGP announcements; reserved/unrouted allocation within the DNIC-ASBLK-00721-00726 DoD block [Confirmed] — https://bgp.he.net/AS726

Related ASNs

AS721–AS725 (siblings in the same DNIC-ASBLK-00721-00726 block) [Confirmed]; AS749 and AS8003 are separate DoD-registered ASNs referenced in NANOG community discussion of DoD "squat space" announcements, not directly operationally tied to AS726 [Likely] — https://rdap.arin.net/registry/autnum/726, https://community.nanog.org/t/squat-space-is-now-being-advertised-by-as-749-dod-network-information-center/54395

Analyst note

Dormant/unannounced DoD ASN within a reserved DNIC block. No dedicated per-ASN operator page exists; RDAP is the only first-party public record. The autnum's top-level RDAP registration date is genuinely absent (only a last-changed timestamp), distinct from several decoy entity-level dates and a third-party epoch artifact — allocated_date is correctly left Unknown rather than nulled on a "non-first-party" rationale or guessed from a decoy.