ASN Data: The Most Underused Field in IP Intelligence

# ASN Data: The Most Underused Field in IP Intelligence

Most teams read the country field and stop. The ASN is frequently the more useful number.

What an ASN is

An autonomous system is a network under one routing policy — an ISP, a hosting provider, a university, a large enterprise. Every announced IP block belongs to one. The ASN tells you who operates the connection, which is far more stable than where the packets appear to originate.

Why it is powerful

• Stability. Address blocks move between customers; the operating network changes far less often.
• Behavioural grouping. Signups from a single hosting ASN in a short window is a much stronger fraud signal than a shared city.
• Explainability. "Blocked because AS14061 is a cloud provider" is a sentence a risk analyst can defend. "Blocked because the city looked odd" is not.

Practical uses

Fraud velocity. Count events per ASN per hour. Residential ISPs have broad, boring distributions. Abuse concentrates.

Bot separation in analytics. Exclude hosting ASNs from engagement metrics and your conversion rates suddenly make sense.

Support triage. Repeated complaints from one ASN usually means a peering or routing problem, not a bug in your app.

Capacity planning. Knowing which carriers your users arrive on tells you where to add a POP.

Reading the ASN type

Guarda returns the ASN, the organisation name and a connection type (residential, mobile, business, hosting). The type is what you build rules on; the name is what you show a human reviewing the case. Together they answer "is this a person on a home connection or a process in a rack?" — the question most fraud rules are really asking.

A caution

Some ASNs are mixed. A large carrier can host both consumer broadband and rented servers. Never treat ASN alone as a verdict; combine it with the classification and the risk score, and keep an allowlist for the corporate networks your own customers use.