Network · AS4373

AS4373 Online Computer Library Center

AS4373 (Online Computer Library Center) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS4373

  • OwnerOnline Computer Library Center
  • KindInternet service provider
  • Servers, not peopleno
  • IPv4 addresses72,704
  • IPv4 ranges16
  • IPv6 ranges0
Risk score0

Nothing suspicious found.

Largest IPv4 ranges

  • 132.174.0.0/16
  • 206.107.40.0/21
  • 204.152.100.0/22
  • 205.160.168.0/23
  • 198.137.190.0/23
  • 154.59.124.0/23
  • 38.117.94.0/24
  • 204.17.227.0/24
  • 204.152.104.0/24
  • 199.164.217.0/24
  • 198.187.191.0/24
  • 198.137.189.0/24

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

Check an IP address →

Detect it in code

Spot AS4373 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 AS4373

Is AS4373 a datacenter or VPN network?

AS4373 (Online Computer Library Center) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS4373?

AS4373 is registered to Online Computer Library Center. It announces about 72,704 IPv4 addresses.

How do I detect traffic from AS4373?

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.