101.4.0.0/14

Currently announced by AS4538 CERNET-CN, in the routed prefix 101.4.0.0/14.

Current ASN: AS4538; CERNET-CN
Routed prefix: 101.4.0.0/14; Most specific route covering this prefix
ASNs over time: 1; 1 announcement record
RIR allocation: APNIC; China · 101.4.0.0/14

Routing data · Nov 8, 2026, 10:26 UTC

ASN historyEvery routed prefix covering 101.4.0.0/14

Prefix	ASN	Name	Registered country	First seen (UTC)	Last seen (UTC)	Status
101.4.0.0/14	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing

More specific routes46 total

Prefix	ASN	Name	Registered country	First seen (UTC)	Last seen (UTC)	Status
101.4.0.0/20	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.2.0/24	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.16.0/20	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.32.0/20	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.48.0/21	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.56.0/24	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.63.0/24	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.64.0/20	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.128.0/24	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.140.0/24	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.156.0/24	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.192.0/18	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.5.0.0/16	AS24348	CERNET2 IX at Tsinghua University	China	Before monitoring	2026-11-08 10:26	Announcing
101.5.0.0/16	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.5.0.0/17	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.5.0.0/18	AS4538	CERNET-CN	China	2026-11-02 18:22	2026-11-08 10:26	Announcing
101.5.24.0/21	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.5.40.0/21	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.5.64.0/18	AS4538	CERNET-CN	China	2026-11-02 18:22	2026-11-08 10:26	Announcing
101.5.128.0/17	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.5.128.0/18	AS4538	CERNET-CN	China	2026-11-02 14:22	2026-11-08 10:26	Announcing
101.5.128.0/21	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.5.136.0/21	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.5.192.0/18	AS4538	CERNET-CN	China	2026-11-02 18:22	2026-11-08 10:26	Announcing
101.6.0.0/16	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.6.0.0/16	AS24348	CERNET2 IX at Tsinghua University	China	Before monitoring	2026-11-08 10:26	Announcing
101.6.0.0/17	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.6.0.0/18	AS4538	CERNET-CN	China	2026-11-02 18:22	2026-11-08 10:26	Announcing
101.6.6.0/24	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.6.8.0/21	AS4538	CERNET-CN	China	2026-11-02 18:22	2026-11-08 10:26	Announcing
101.6.16.0/23	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.6.64.0/18	AS4538	CERNET-CN	China	2026-11-02 18:22	2026-11-08 10:26	Announcing
101.6.128.0/17	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.6.128.0/18	AS4538	CERNET-CN	China	2026-11-02 18:22	2026-11-08 10:26	Announcing
101.6.192.0/18	AS4538	CERNET-CN	China	2026-11-02 18:22	2026-11-08 10:26	Announcing
101.7.0.0/22	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.7.7.0/24	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.7.7.0/24	AS9405	Test platform Service Center	China	Before monitoring	2026-11-08 10:26	Announcing
101.7.64.0/18	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.7.128.0/18	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.7.160.0/24	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.7.192.0/20	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.7.208.0/22	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.7.224.0/20	AS4538	CERNET-CN	China	Before monitoring	2026-11-08 10:26	Announcing
101.4.160.0/23	AS4538	CERNET-CN	China	Before monitoring	2026-11-02 12:24	Stopped
101.4.162.0/23	AS4538	CERNET-CN	China	Before monitoring	2026-11-02 12:24	Stopped

Change logAll changes

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

Look up another address

RIR allocation record

Registry: APNIC
Allocated block: 101.4.0.0/14
Country: China
Allocation date: 2010-12-09
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.