Network · AS37917

AS37917 University of Tsukuba

AS37917 (University of Tsukuba) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS37917

OwnerUniversity of Tsukuba
KindInternet service provider
Servers, not peopleno
IPv4 addresses132,096
IPv4 ranges3
IPv6 ranges0

Risk score0

Nothing suspicious found.

Largest IPv4 ranges

133.51.0.0/16
130.158.0.0/16
163.220.252.0/22

Ranges and owner from DB-IP (CC BY 4.0), updated 2026-10-22.

Check an IP address →

Detect it in code

Spot AS37917 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 AS37917

Is AS37917 a datacenter or VPN network?

AS37917 (University of Tsukuba) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS37917?

AS37917 is registered to University of Tsukuba. It announces about 132,096 IPv4 addresses.

How do I detect traffic from AS37917?

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.