Home Prefix Lookup66.243.0.0/17

66.243.0.0/17 - Level 3 Parent (AS3356)

IPv4ARINallocatedAS3356LEVEL3 - Level 3 Parent, LLCNo ROA

CIDR

66.243.0.0/17

IP Version

IPv4

Addresses

32.7K

Mask

/17 (255.255.128.0)

Country

🇺🇸 United States

City

Broomfield (Interlocken)

RIR

ARIN

Status

allocated

Allocated

2002-03-04

Announced BGP Routes

1 of 1 route

RPKI:

IRR:

Swipe sideways to see all columns →

Prefix	Origin AS	RPKI	IRR	Last Seen
66.243.0.0/17	AS3356 LEVEL3 - Level 3 Parent, LLC	No ROA	-	2026-10-12

Transfer History

Registry transfers of 66.243.0.0/17, blocks inside it, or blocks containing it.

66.243.0.0/17M&A · 2018-02-20
Level 3 Communications, Inc.
🇺🇸 US ARIN
→
Level 3 Parent, LLC
🇺🇸 US ARIN

Date	Resource	From	To	Type
2018-02-20	66.243.0.0/17	Level 3 Communications, Inc. 🇺🇸 US ARIN	Level 3 Parent, LLC 🇺🇸 US ARIN	M&A

Origin ASN

AS3356

LEVEL3 - Level 3 Parent, LLC

Related Prefixes

More prefixes of AS3356

All prefixes of AS3356 →

Geolocation

Country🇺🇸United StatesUS

RegionColorado

CityBroomfield (Interlocken)

Coordinates39.9217, -105.1440 ↗

Learn more

RPKI and ROAs explainedWhat RPKI valid, invalid and no ROA mean
RPKI validatorCheck ROA coverage for any prefix or ASN
What is BGP?How prefixes are announced and routed
More-specific prefixesGlossary: covering and more-specific routes
IPv4 transfers in the ARIN regionWho bought and sold address space recently

API

Open

GEThttps://api.ipctl.io/v1/prefix/66.243.0.0/17

Returns prefix allocation, BGP routes, and more-specific subnets.

curl -s "https://api.ipctl.io/v1/prefix/66.243.0.0/17" | jq

External Links

RIPEstat