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AS81
NCREN

AS81 announces 2,023,168 IPv4 addresses across 70 routed ranges, registered in US. Figures come from the public global routing table and are refreshed daily.

2M addressesIPv4 space announced
70Routed ranges
USRegistry country

Is AS81 datacenter space?

Not according to the nine cloud and CDN providers whose published range lists we track. That is a statement about those specific lists, not proof the space is residential — plenty of hosting companies never publish machine-readable ranges, and this AS may well be one of them.

The reliable way to classify a specific address is to check it directly rather than to infer from the AS. The free lookup tool returns live tunnel and datacenter signals for any address.

What an AS number does and does not tell you

An autonomous system number identifies who announces a block of addresses to the internet's routing table. It is an organisational fact, and a durable one — useful for attributing traffic to a hosting company, a carrier, or a university.

It is not a risk signal. A residential ISP's AS carries the household traffic of millions of ordinary customers and, at the same time, whatever residential proxy exits have been installed on those customers' devices. A hosting AS carries scrapers and legitimate server-to-server integrations in the same ranges. Scoring an address on the reputation of its AS produces exactly the false positives that make fraud tooling untrustworthy.

Sentinel does not feed AS names or routing data into its risk score. Tunnel detection comes from live network intelligence, and the dch signal comes from provider-published ranges. This directory exists to answer "who announces this address," which is a different and genuinely useful question.

Announced IPv4 ranges

All 70 announced ranges.

Range startRange endAddresses
128.109.0.0128.109.255.25565,536
152.4.0.0152.4.255.25565,536
152.6.0.0152.6.255.25565,536
152.8.0.0152.12.255.255327,680
152.18.0.0152.18.255.25565,536
152.20.0.0152.21.255.255131,072
152.22.2.0152.22.55.25513,824
152.22.56.0152.22.87.2558,192
152.22.88.0152.22.223.25534,816
152.26.0.0152.26.16.2554,352
152.26.17.0152.26.30.2553,584
152.26.32.0152.26.44.2553,328
152.26.45.0152.26.54.2552,560
152.26.56.0152.26.60.2551,280
152.26.61.0152.26.69.2552,304
152.26.70.0152.26.87.2554,608
152.26.92.0152.27.12.25545,312
152.27.13.0152.27.73.25515,616
152.27.75.0152.28.1.25546,848
152.28.2.0152.30.10.255133,376
152.30.11.0152.30.92.25520,992
152.30.93.0152.30.95.255768
152.30.96.0152.30.255.25540,960
152.32.0.0152.32.63.25516,384
152.35.0.0152.35.255.25565,536
152.38.0.0152.38.95.25524,576
152.38.160.0152.38.255.25524,576
152.40.64.0152.40.255.25549,152
152.42.64.0152.42.127.25516,384
152.45.0.0152.45.15.2554,096
152.45.16.0152.45.20.2551,280
152.45.21.0152.46.9.25562,720
152.46.10.0152.46.39.2557,680
152.46.40.0152.49.255.255251,904
152.54.0.0152.54.255.25565,536
152.60.0.0152.60.4.2551,280
152.60.5.0152.60.255.25564,256
185.83.159.0185.83.159.255256
192.101.21.0192.101.22.255512
192.101.23.0192.101.24.255512
192.137.210.0192.137.210.255256
192.154.33.0192.154.33.255256
192.154.43.0192.154.43.255256
192.154.48.0192.154.48.255256
192.154.55.0192.154.55.255256
192.154.58.0192.154.58.255256
192.154.60.0192.154.61.255512
192.154.66.0192.154.66.255256
192.154.76.0192.154.77.255512
192.154.95.0192.154.95.255256
192.189.244.0192.189.244.255256
198.85.0.0198.85.116.25529,952
198.85.118.0198.85.211.25524,064
198.85.213.0198.85.219.2551,792
198.85.221.0198.85.222.255512
198.85.224.0198.85.227.2551,024
198.85.229.0198.85.229.255256
198.85.232.0198.86.28.25513,568
198.86.30.0198.86.247.25555,808
198.86.248.0198.86.255.2552,048
204.84.0.0204.84.3.2551,024
204.84.12.0204.84.65.25513,824
204.84.67.0204.84.95.2557,424
204.84.96.0204.84.237.25536,352
204.84.240.0204.84.243.2551,024
204.84.248.0204.84.251.2551,024
204.85.0.0204.85.175.25545,056
204.85.192.0204.85.255.25516,384
206.107.110.0206.107.110.255256
206.211.64.0206.211.95.2558,192

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