Network · AS1103

AS1103 SURF B.V.

AS1103 (SURF B.V.) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS1103

OwnerSURF B.V.
KindInternet service provider
Servers, not peopleno
IPv4 addresses6,665,984
IPv4 ranges124
IPv6 ranges38

Risk score0

Nothing suspicious found.

Largest IPv4 ranges

145.160.0.0/12
145.144.0.0/13
145.88.0.0/14
145.140.0.0/14
145.120.0.0/14
145.92.0.0/15
145.74.0.0/15
145.48.0.0/15
145.38.0.0/15
145.28.0.0/15
145.2.0.0/15
145.136.0.0/15

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

Check an IP address →

Detect it in code

Spot AS1103 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 AS1103

Is AS1103 a datacenter or VPN network?

AS1103 (SURF B.V.) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS1103?

AS1103 is registered to SURF B.V.. It announces about 6,665,984 IPv4 addresses.

How do I detect traffic from AS1103?

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.