Network · AS39961

AS39961 San Francisco Department of Telecommunications and Information Services

AS39961 (San Francisco Department of Telecommunications and Information Services) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Network check ASN

AS39961

  • OwnerSan Francisco Department of Telecommun
  • KindInternet service provider
  • Servers, not peopleno
  • IPv4 addresses58,368
  • IPv4 ranges6
  • IPv6 ranges0
Risk score0

Nothing suspicious found.

Largest IPv4 ranges

  • 208.121.128.0/17
  • 208.121.64.0/18
  • 208.121.32.0/19
  • 208.121.0.0/23
  • 208.121.6.0/24
  • 208.121.5.0/24

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

Check an IP address →

Detect it in code

Spot AS39961 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 AS39961

Is AS39961 a datacenter or VPN network?

AS39961 (San Francisco Department of Telecommunications and Information Services) looks like an internet service provider, so its addresses are mostly real home, business or mobile connections.

Who owns AS39961?

AS39961 is registered to San Francisco Department of Telecommunications and Information Services. It announces about 58,368 IPv4 addresses.

How do I detect traffic from AS39961?

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.