Network · AS25979

AS25979 CITY OF MADISON

AS25979 (CITY OF MADISON) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS25979

OwnerCITY OF MADISON
KindInternet service provider
Servers, not peopleno
IPv4 addresses4,096
IPv4 ranges1
IPv6 ranges1

Risk score0

Nothing suspicious found.

Largest IPv4 ranges

204.147.0.0/20

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

Check an IP address →

Detect it in code

Spot AS25979 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 AS25979

Is AS25979 a datacenter or VPN network?

AS25979 (CITY OF MADISON) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS25979?

AS25979 is registered to CITY OF MADISON. It announces about 4,096 IPv4 addresses.

How do I detect traffic from AS25979?

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.