Intro #
IP2Location is glad to announce the introduction of new Autonomous System data in both the IP2Location DB26 database and the IP2Location.io API. In the DB26, previously the data included the Autonomous System (AS) name and Autonomous System Number (ASN). Starting in September 2025, existing & new DB26 users can have access to more AS data like AS domain name, AS CIDR and the AS usage type. At the same time, the IP2Location.io API users with a Security Plan subscription will have access to similar data which will be grouped under the as_info section of the JSON result.
What is an Autonomous System (AS)? #
An Autonomous System (AS) is a collection of IP address ranges (prefixes/CIDRs) that are all managed by the same network operator (like an ISP, cloud provider, university, or enterprise). Think of it as a large network under one administration, with its own routing policies.
What is an Autonomous System Number (ASN)? #
An ASN is the unique number assigned to each AS. It identifies that network on the Internet.
Example:
Google A15169
Cloudflare A13335
Mullvad VPN A197922
Why do ASNs exist? #
The Internet is made of tens of thousands of ASes. They exchange routes using BGP (Border Gateway Protocol).
ASN tells routers:
“This IP range belongs to ASXXXX, and here’s how to reach it.”
Common Uses for the AS data #
Security & Threat Intelligence #
Using the AS data, you can identify the organization behind the IP. E.g., If you look up an IP and see it belongs to AS15169, you immediately know that’s Google, based on the AS domain value. This is more reliable than just “WHOIS contact”, because the ASN is what’s actually being routed.
Furthermore, the AS Usage Type is a critical signal for identifying potential proxy or VPN traffic. A usage type labeled as ‘DCH’ (Data Center/Hosting) indicates that the IP originates from a server farm rather than a residential or mobile provider. Because legitimate customers typically browse from residential (RES) or mobile (MOB) networks, traffic from a data center during a checkout or sensitive transaction often indicates a user masking their true location. In high-stakes environments, such as payment processing or account logins, flagging or blocking ‘DCH’ traffic is a highly effective strategy for preventing automated fraud and account takeovers.
Being able to block all traffic from data center or hosting ASNs (common for VPNs, scrapers & bots), you can rest easy about malicious actors trying to breach your system or steal your data. These bad actors often rely on certain ASNs or CIDRs as they belong to cheap hosts or bulletproof providers.
Having the AS CIDR is very useful whenever you’re trying to block Distributed Denial of Service (DDoS) attacks. You can easily input the CIDR into firewalls and other security applications to mitigate attacks.
Network Optimization #
If you run an online service, you can filter routes or prioritize traffic differently depending on ASN (e.g., optimize for users on residential ISPs).
Fraud Screening #
ASN data serves as a foundational layer in online order fraud screening. Merchants can perform high-fidelity geolocation and infrastructure checks by mapping a customer’s IP address to its corresponding ASN. For instance, if a customer provides a shipping address in Malaysia but their IP address originates from an AWS (Amazon) ASN based in Singapore, this creates a clear discrepancy. Such a mismatch often indicates the use of a VPN or proxy to mask the user’s true location, justifying an immediate flag for manual review or automated rejection to prevent potential payment fraud.
Similarly, the AS Usage Type provides a vital sanity check for user intent. A ‘DCH’ (Data Center) label signals that the connection originates from a server environment rather than a household. When a visitor claims to be a residential ‘home shopper’ while connecting through a data center, they strongly indicate the use of an anonymizing proxy or a sophisticated bot. Your system should automatically flag these transactions for manual review or secondary authentication (such as 3D Secure), as they carry a significantly higher probability of fraud.
Conclusion #
There are many ways to use Autonomous System data and with the addition of the AS CIDR, AS usage type and AS domain name, we are confident that users will be able to fully leverage them to further mitigate attacks and keep fraud to a minimum. Get your latest DB26 database today or subscribe to the IP2Location.io API with the Security Plan.
