Autonomous system
AS5371 AS5371
Unclassified ARIN
IPv4 addresses
144K
141 prefixes
IPv6 prefixes
0
counted as prefixes, not addresses
Countries
1
mostly Unknown
Flagged prefixes
0
none
Summary
US Department of Defense
government military legacy
A US Department of Defense network from the block DNIC-ASBLK-05120-05376,
registered to the DoD Network Information Center (DNIC).
What it's used for
- Operational US Navy networking, and at considerable scale: it originates hundreds of prefixes, essentially all from legacy
205.xspace registered to the Navy Network Information Center (NNIC).
Notable
- A government / military network, not a commercial ISP or host.
- One of the busiest ASNs in the DNIC block by prefix count, announcing many small blocks rather than a few large ones — a pattern that fits a network stitched together from many separately assigned sites.
- The ASN registration is generic to the DoD block, so no specific command or installation is publicly identified.
Interesting
- The Navy's address space is spread across a great many small legacy blocks rather than consolidated into a few aggregates, which is why a single Navy ASN can end up carrying a routing table entry count out of proportion to the amount of address space it actually holds.
This description is AI-generated, best-effort context — not authoritative, and provided without any guarantee of accuracy. Source, and how to suggest an edit.
Address space
Summary
| Country | Name | Prefixes |
|---|---|---|
| Unknown | 141 |
Registry
Allocation record
- Registry
- ARIN
- Handle
AS5120- Registry name
- DNIC-ASBLK-05120-05376
- Registrant
- United States Department of Defense (DoD)
- Abuse contact
- disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil
- Registered
- 1995-05-09
- Last changed
- 2025-09-12
- Status
- active
Reputation
Classification and threat
Unclassified Not in the curated lists. Most of the ~80,000 allocated ASNs are not.
No IC3 indicators Nothing from the FBI IC3 feed.
Threat data is alpha. Absence of an indicator is not evidence of good behaviour, only of absence from this one feed.
Elsewhere