AS620

AS620 is a legacy 16-bit autonomous system number administered by ARIN as part of the block DNIC-ASBLK-00616-00665 (AS616–AS665), registered to the United States Department of Defense (org handle USDDD) and operated on the DoD's behalf by DISA's Columbus, Ohio facility. The ARIN RDAP autnum record's top-level registration event dates the block to 1990-04-19, with a last-changed timestamp of 2025-09-12; this is independently corroborated by bgp.tools, which lists AS620 as "registered since April 19, 1990." Like many ASNs in this DoD block, AS620 is currently dormant on the public Internet: RIPEstat, CAIDA ASRank, bgp.he.net, and bgp.tools all agree it announces zero IPv4 and zero IPv6 prefixes, is seen by none of the 326 (v4) or 322 (v6) RIPE RIS peers, and has a customer cone of exactly one ASN with zero prefixes and zero addresses. No PeeringDB record exists for it, and CAIDA's AS-degree figures show zero customers, peers, or providers, placing it at AS rank 79,459 — near the very bottom of the global ranking. RPKI validation does not apply since no prefixes are announced. No notable public abuse signal was found in Spamhaus, CleanTalk, blocklist aggregators, or NANOG archives, though a direct Spamhaus query was blocked (HTTP 403) and could not be confirmed first-party. A third-party claim linking AS620 to the Navy Network Information Center ("PENS-NET-AS") was checked and found unsupported by both ARIN RDAP and NNIC's own ASN listing, and is not adopted here.

Operator

United States Department of Defense (DoD) — ARIN org handle USDDD, block DNIC-ASBLK-00616-00665 (AS616–AS665) [Confirmed] — https://rdap.arin.net/registry/autnum/620

Country / RIR

US, ARIN [Confirmed] — https://rdap.arin.net/registry/autnum/620

Allocated

1990-04-19 (ARIN RDAP autnum top-level registration event, block-level allocation covering AS616–AS665); last changed 2025-09-12 [Confirmed] — https://rdap.arin.net/registry/autnum/620; corroborated by https://bgp.tools/as/620 ("registered since April 19, 1990")

Org status

active [Confirmed] — ARIN RDAP autnum status field

Operator website / peering policy

Unknown — no operator-official DoD/DISA page identifying AS620 specifically, and no PeeringDB record exists [Unknown] — https://www.disa.mil/network-services (general DISA page only, not AS620-specific)

Abuse / technical contact

disa.columbus.ns.mbx.hostmaster-dod-nic@mail.mil; "Network DoD" group, DISA-Columbus, 300 North James Road, Whitehall, OH 43213; phone +1-844-347-2457 ext2

Security/abuse context (NEUTRAL, DATED)

no notable public abuse signal found as of 2026-07-17 across Spamhaus ASN-DROP references, bad-asn-list/ASN-BlackList/blocklist-abuseipdb aggregators, CleanTalk, and NANOG archives; a direct query to Spamhaus's own lookup returned HTTP 403 and could not be verified first-party, so "clean" rests on absence-of-mention rather than a confirmed negative [Likely] — https://bgp.he.net/AS620, spamhaus.org/blocklists/do-not-route-or-peer/, github.com/bountyyfi/bad-asn-list, github.com/C0nw0nk/ASN-BlackList, cleantalk.org/blacklists/asn, seclists.org/nanog/

Network & routing

Network type

government/military internal network administered by DISA on behalf of DoD; not a commercial ISP/transit/content network [Likely] — no operator-official classification page found beyond registry contact records

Size / routing

NOT announced — 0 IPv4 and 0 IPv6 prefixes across RIPEstat, CAIDA, bgp.he.net, and bgp.tools; 0 of 326 RIS peers (v4) and 0 of 322 (v6) see it; customer cone = singleton (1 ASN, 0 prefixes, 0 addresses)

[Confirmed] — RIPEstat routing-status/announced-prefixes (stat.ripe.net, resource=620), CAIDA ASRank

Peering / upstreams

no PeeringDB record exists for AS620 (query returns 404); 0 observed peers/upstreams in CAIDA AS-degree (customer 0, peer 0, provider 0) and on bgp.he.net/bgp.tools [Confirmed no peers observed; Unknown re: any formal peering policy] — https://www.peeringdb.com/asn/620, CAIDA ASRank

RPKI

not assessable — AS620 announces no prefixes, so there are no ROAs to validate [Confirmed] — RIPEstat rpki-validation (skipped, no prefix supplied), https://bgp.he.net/AS620

CAIDA AS rank

79,459 (near the bottom of the global ranking, reflecting zero routing participation) [Confirmed] — CAIDA ASRank (asn=620)

Registrant address

United States Department of Defense (DoD), 3990 E. Broad Street, Columbus, OH 43218 [Confirmed] — ARIN RDAP entity USDDD (https://rdap.arin.net/registry/autnum/620)

Community corroboration

no NANOG list discussions, documented outages, or community reputation signals found specifically naming AS620 [Unknown] — searches of NANOG archives (seclists.org/nanog) and BGP-incident trackers

Analyst note

a WebSearch summary claimed AS620 = "PENS-NET-AS" assigned to the Navy Network Information Center (NNIC); checked against networksdb.io's NNIC ASN listing, which does NOT include AS620, and against ARIN RDAP, which shows a generic DoD org (USDDD) rather than a Navy-specific one — flagged as an unsupported/contradicted claim and NOT adopted.