Autonomous System

AS81 MCNC

ISPActiveUnited StatesARIN

AS81 (NCREN) is an ISP network operated by MCNC in United States, registered with ARIN. It has 134 IPv4 prefixes with 2,056,448 addresses and 4 IPv6 prefixes, which makes it the 252nd largest of 82,200 active autonomous systems by IPv4 space.

IPv4 addresses2,056,448in 134 prefixes
IPv6 prefixes4≈ 1.3 × 10³⁰ addresses
Size rank#252of 82,200 active ASNs
Abuser scoreVery Lowunder 0.01% of its addresses flagged · method

Details

OrganizationMCNC
AS nameNCREN
Websitemcnc.org
Country United States (US)
Network typeISP
RegistryARIN
Abuse contactabuse@mcnc.org
Registered1986-08-07
Last updated2026-06-10

IPv4 prefixes

134 prefixes · 2,056,448 addresses
NetworkAddressesFirst – last address
204.84.0.0/15131,072204.84.0.0 – 204.85.255.255
128.109.0.0/1665,536128.109.0.0 – 128.109.255.255
152.4.0.0/1665,536152.4.0.0 – 152.4.255.255
152.6.0.0/1665,536152.6.0.0 – 152.6.255.255
152.8.0.0/1665,536152.8.0.0 – 152.8.255.255
152.9.0.0/1665,536152.9.0.0 – 152.9.255.255
152.10.0.0/1665,536152.10.0.0 – 152.10.255.255
152.11.0.0/1665,536152.11.0.0 – 152.11.255.255
152.12.0.0/1665,536152.12.0.0 – 152.12.255.255
152.18.0.0/1665,536152.18.0.0 – 152.18.255.255
152.20.0.0/1665,536152.20.0.0 – 152.20.255.255
152.21.0.0/1665,536152.21.0.0 – 152.21.255.255
152.22.0.0/1665,536152.22.0.0 – 152.22.255.255
152.26.0.0/1665,536152.26.0.0 – 152.26.255.255
152.27.0.0/1665,536152.27.0.0 – 152.27.255.255
152.28.0.0/1665,536152.28.0.0 – 152.28.255.255
152.29.0.0/1665,536152.29.0.0 – 152.29.255.255
152.30.0.0/1665,536152.30.0.0 – 152.30.255.255
152.40.0.0/1665,536152.40.0.0 – 152.40.255.255
152.45.0.0/1665,536152.45.0.0 – 152.45.255.255
152.46.0.0/1665,536152.46.0.0 – 152.46.255.255
152.47.0.0/1665,536152.47.0.0 – 152.47.255.255
152.48.0.0/1665,536152.48.0.0 – 152.48.255.255
152.49.0.0/1665,536152.49.0.0 – 152.49.255.255
152.54.0.0/1665,536152.54.0.0 – 152.54.255.255
The 25 largest of 134. The API and the database have all of them.

IPv6 prefixes

4 prefixes
  • 2600:2700::/28
  • 2610:28::/32
  • 2602:f64d::/40
  • 2602:f6b8::/40

Query AS81 with the API

The ASN lookup returns everything on this page as JSON, including every prefix. ASN lookups need an API key: a free account comes with 1,000 requests a day. 

curl "https://api.ipapi.is/?q=AS81&key=YOUR_API_KEY"

Any address in its prefixes resolves to AS81, with or without a key:

curl "https://api.ipapi.is/?q=204.84.0.1"

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