Autonomous System

AS201727 — B4(CZ)

Last fetched Wed, 20 May 2026 21:54:28 GMT

AS201727 is an Autonomous System operated by B4 and registered in CZ. As of Wed, 20 May 2026 21:54:28 GMT, it announces 3 routed IP prefixes and peers with 1 other Autonomous System in the WhisperGraph BGP dataset.

Nutrition Label

Routing footprint

AS201727 announces 3 distinct routed prefixes. The 3-prefix sample below links to per-prefix pages with full conflict and reverse-DNS detail.

Peering ecosystem

1 distinct peers via BGP. The first 1 are listed below.

Peer ASN	Operator	Country
AS15935	HA-VEL-LOCAL-AS Czech republic	CZ

Blast radius

Approximate count of dependent hostnames if AS201727 disappeared from the routing table.

~205 hostnames depend on this network.Sampled from 10 prefixes, snapshot Wed, 20 May 2026 21:54:28 GMT.

MOAS / hijack watch

Prefixes routed by AS201727 that another Autonomous System also announces. A non-empty list is one of the strongest BGP-hijack signals available without active probes.

No active MOAS conflicts. Every prefix announced by AS201727 is unique to AS201727 in the current routing snapshot.

Threat posture

Pivot deeper into the graph from AS201727.

Cypher and MCP

Reproduce the headline metric directly against graph.whisper.security:

MATCH (a:ASN {name: "AS201727"})-[:HAS_NAME]->(n:ASN_NAME)
OPTIONAL MATCH (a)-[:HAS_COUNTRY]->(c:COUNTRY)
RETURN a.name AS asn, n.name AS operator, c.name AS country

Or query Whisper from your own LLM workflow via the Whisper MCP server.