Network · AS51791

AS51791 Crestu Teknoloji Dijital Hizmetler Limited Sirketi

AS51791 (Crestu Teknoloji Dijital Hizmetler Limited Sirketi) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS51791

OwnerCrestu Teknoloji Dijital Hizmetler Lim
KindInternet service provider
Servers, not peopleno
IPv4 addresses768
IPv4 ranges2
IPv6 ranges17

Risk score0

Nothing suspicious found.

Largest IPv4 ranges

153.56.128.0/23
153.56.130.0/24

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

Check an IP address →

Detect it in code

Spot AS51791 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 AS51791

Is AS51791 a datacenter or VPN network?

AS51791 (Crestu Teknoloji Dijital Hizmetler Limited Sirketi) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS51791?

AS51791 is registered to Crestu Teknoloji Dijital Hizmetler Limited Sirketi. It announces about 768 IPv4 addresses.

How do I detect traffic from AS51791?

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.