204.183.80.0/20

Currently announced jointly by AS174 Cogent Communications, Inc., AS6372 DCANet, in the routed prefix 204.183.80.0/20.

Current ASN: AS174 AS6372; Cogent Communications, Inc.
Routed prefix: 204.183.80.0/20; Most specific route covering this prefix
ASNs over time: 2; 3 announcement records
RIR allocation: ARIN; United States · 204.180.0.0/14

Routing data · Nov 11, 2026, 18:22 UTC

ASN historyEvery routed prefix covering 204.183.80.0/20

Prefix	ASN	Name	Registered country	First seen (UTC)	Last seen (UTC)	Status
204.183.80.0/20	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.80.0/20	AS6372	DCANet	United States	Before monitoring	2026-11-11 18:22	Announcing
204.180.0.0/14	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing

More specific routes16 total

Prefix	ASN	Name	Registered country	First seen (UTC)	Last seen (UTC)	Status
204.183.80.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.81.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.82.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.83.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.84.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.85.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.86.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.87.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.88.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.89.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.90.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.91.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.92.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.93.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.94.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing
204.183.95.0/24	AS174	Cogent Communications, Inc.	United States	Before monitoring	2026-11-11 18:22	Announcing

Change logAll changes

The routes covering this address have had no origin changes since ASNBase started monitoring.

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RIR allocation record

Registry: ARIN
Allocated block: 204.180.0.0/14
Country: United States
Allocation date: 1994-10-18
Status: allocated

From the RIRs’ delegated statistics files. Shows where the addresses are registered, not where they are used.

How monitoring works

Every 2 hours ASNBase takes the bgp.tools global routing table (prefix → origin ASN) and compares it with the previous one. The detected time is the time of that comparison; the actual change can be up to about 2 hours earlier.
Only routes seen by more than 100 bgp.tools peers are listed as changes; routes with less visibility are only kept in the history.
A new announcement counts only if it is still in the next routing table, and a withdrawal only if the prefix is missing from two tables in a row, so short flaps are ignored.
ASNBase has been monitoring since 2026-10-19. “Before monitoring” under “First seen” means the route was already announced when monitoring started; the earlier date is unknown.
Prefixes first seen during the first day of monitoring do not count as new announcements: most of them were simply missing from the table at the moment monitoring started.
Countries and regions follow the ASN’s registration, not the actual location of the IP addresses.