Network · AS31911

AS31911 Blood Systems, Inc.

AS31911 (Blood Systems, Inc.) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS31911

OwnerBlood Systems, Inc.
KindInternet service provider
Servers, not peopleno
IPv4 addresses1,536
IPv4 ranges4
IPv6 ranges0

Risk score0

Nothing suspicious found.

Largest IPv4 ranges

205.143.156.0/23
205.143.154.0/23
204.124.21.0/24
198.207.194.0/24

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

Check an IP address →

Detect it in code

Spot AS31911 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 AS31911

Is AS31911 a datacenter or VPN network?

AS31911 (Blood Systems, Inc.) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS31911?

AS31911 is registered to Blood Systems, Inc.. It announces about 1,536 IPv4 addresses.

How do I detect traffic from AS31911?

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.