187.137.128.0/21

Currently announced by AS8151 Uninet S.A. de C.V., in the routed prefix 187.137.128.0/21.

Routing data · Nov 1, 2026, 20:20 UTC

ASN historyEvery routed prefix covering 187.137.128.0/21

Prefix	ASN	Name	Registered country	First seen (UTC)	Last seen (UTC)	Status
187.137.128.0/21	AS8151	Uninet S.A. de C.V.	Mexico	2026-10-29 22:21	2026-11-01 20:20	Announcing
187.137.128.0/19	AS8151	Uninet S.A. de C.V.	Mexico	Before monitoring	2026-11-01 20:20	Announcing

No more specific routes inside this prefix.

Detected (UTC)	Prefix	Change	ASN	Name	Previous ASN	Country
2026-10-29 22:21	187.137.128.0/21	New announcement	AS8151	Uninet S.A. de C.V.	—	Mexico

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

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.