Network · AS721

AS721 DoD Network Information Center

AS721 (DoD Network Information Center) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS721

OwnerDoD Network Information Center
KindInternet service provider
Servers, not peopleno
IPv4 addresses28,432,896
IPv4 ranges5,292
IPv6 ranges19

Risk score0

Nothing suspicious found.

Largest IPv4 ranges

55.128.0.0/11
55.240.0.0/12
55.160.0.0/12
55.112.0.0/12
55.232.0.0/13
55.216.0.0/13
55.200.0.0/13
55.104.0.0/13
55.228.0.0/14
55.212.0.0/14
55.184.0.0/14
55.180.0.0/14

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

Check an IP address →

Detect it in code

Spot AS721 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 AS721

Is AS721 a datacenter or VPN network?

AS721 (DoD Network Information Center) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS721?

AS721 is registered to DoD Network Information Center. It announces about 28,432,896 IPv4 addresses.

How do I detect traffic from AS721?

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.