Network · AS59

AS59 University of Wisconsin Madison

AS59 (University of Wisconsin Madison) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS59

OwnerUniversity of Wisconsin Madison
KindInternet service provider
Servers, not peopleno
IPv4 addresses331,008
IPv4 ranges12
IPv6 ranges1

Risk score0

Nothing suspicious found.

Largest IPv4 ranges

128.104.0.0/15
72.33.0.0/16
146.151.0.0/16
144.92.0.0/16
205.213.248.0/22
198.51.246.0/23
198.133.224.0/23
198.51.254.0/24
192.86.79.0/24
192.12.224.0/24
192.12.223.0/24
192.12.220.0/24

Ranges and owner from DB-IP (CC BY 4.0), updated 2026-10-21.

Check an IP address →

Detect it in code

Spot AS59 traffic at signup.

Send the visitor's IP. The response includes the ASN, the owner and flags.hosting.

curl https://veqen-app.com/v1/ip/check \
  -H "Authorization: Bearer $VEQEN_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"ip": "203.0.113.7"}'

import os, requests

r = requests.post(
    "https://veqen-app.com/v1/ip/check",
    headers={"Authorization": f"Bearer {os.environ['VEQEN_API_KEY']}"},
    json={"ip": "203.0.113.7"},
    timeout=10,
)
result = r.json()
print(result["risk"]["verdict"], result["risk"]["reasons"])

const res = await fetch("https://veqen-app.com/v1/ip/check", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.VEQEN_API_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({"ip": "203.0.113.7"}),
});
const result = await res.json();
console.log(result.risk.verdict, result.risk.reasons);

Questions

About AS59

Is AS59 a datacenter or VPN network?

AS59 (University of Wisconsin Madison) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS59?

AS59 is registered to University of Wisconsin Madison. It announces about 331,008 IPv4 addresses.

How do I detect traffic from AS59?

Call the Veqen IP check with the visitor's address. The response includes the ASN, the owner and whether the network is a datacenter, VPN network, relay or ISP.