Autonomous System
AS21965 — HIGHMARK - Highmark Inc(US)
Last fetched
AS21965 is an Autonomous System operated by HIGHMARK - Highmark Inc and registered in US. As of Thu, 21 May 2026 10:20:36 GMT, it announces 22 routed IP prefixes and peers with 5 other Autonomous Systems in the WhisperGraph BGP dataset.
Nutrition Label
Routing footprint
AS21965 announces 22 distinct routed prefixes. The 22-prefix sample below links to per-prefix pages with full conflict and reverse-DNS detail.
- 157.154.3.0/24
- 157.154.4.0/24
- 157.154.5.0/24
- 157.154.6.0/24
- 157.154.7.0/24
- 157.154.8.0/24
- 157.154.11.0/24
- 157.154.14.0/24
- 157.154.20.0/24
- 167.164.3.0/24
- 167.164.4.0/24
- 167.164.5.0/24
- 167.164.6.0/24
- 167.164.7.0/24
- 167.164.8.0/24
- 167.164.11.0/24
- 167.164.14.0/24
- 167.164.20.0/24
- 192.152.123.0/24
- 199.190.160.0/24
- 199.190.163.0/24
- 199.190.164.0/24
Peering ecosystem
5 distinct peers via BGP. The first 5 are listed below.
Blast radius
Approximate count of dependent hostnames if AS21965 disappeared from the routing table.
~3,491 hostnames depend on this network.Sampled from 10 prefixes, snapshot Thu, 21 May 2026 10:20:36 GMT.
MOAS / hijack watch
Prefixes routed by AS21965 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 AS21965 is unique to AS21965 in the current routing snapshot.
Threat posture
Related pages
Pivot deeper into the graph from AS21965.
Cypher and MCP
Reproduce the headline metric directly against graph.whisper.security:
MATCH (a:ASN {name: "AS21965"})-[:HAS_NAME]->(n:ASN_NAME)
OPTIONAL MATCH (a)-[:HAS_COUNTRY]->(c:COUNTRY)
RETURN a.name AS asn, n.name AS operator, c.name AS countryOr query Whisper from your own LLM workflow via the Whisper MCP server.