What is an ASN? Network operators and how to check

An ASN identifies an Autonomous System (AS), a network unit that exchanges routing information on the internet. It helps you understand which network an IP address is associated with; it does not identify an individual user or device.

IP address, ASN, and operator name

• An IP address identifies a source or destination for communication.
• An AS is a group of networks operated under a common routing policy.
• An ASN is the number assigned to that AS. NetKarte displays it with an “AS” prefix.
• The network operator is the organization associated with the IP's ASN, not necessarily the brand of the internet service you purchased.

For example, in “AS64496”, “AS” indicates the type and “64496” is the number. This documentation-reserved number is an illustrative example, not a connection measured by NetKarte.

Why does the name differ from my internet provider?

A retail service brand and the organization operating its network can be different. With a corporate gateway or VPN, the result may describe the exit IP rather than your local connection.

A different name alone does not establish VPN use or an unauthorized connection. First check whether you looked up your current source IP or a different target.

How to check with NetKarte

1. In Network diagnostics, check your current IP address and whether it is IPv4 or IPv6.
2. Read the ASN together with the network operator in the IP & connection card.
3. To investigate another IP, enter it in IP Information Lookup.
4. For the registered organization or network range, check the separate RDAP / WHOIS registration section.

The ASN organization and registration organization do not come from the same source. A difference does not immediately establish that either is incorrect.

How the result is obtained—and its limits

NetKarte reads the ASN and organization associated with an IP from its local GeoLite2 ASN database. It does not measure current BGP routes for each search; the result reflects the database's contents.

Two IPs with the same ASN do not necessarily share a route, speed, user, or location. A larger or smaller number is not a ranking of connection quality or safety.

If no matching information exists or the database is unavailable, NetKarte cannot display an ASN. Separate the lookup status from actual connectivity: a missing ASN alone does not establish a connection failure.