IP to ASN Mapping Whois Service

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IP to ASN Mapping Service with History

There are several services on the Internet to map IP addresses to their corresponding BGP AS number like the renowned IP to ASN mapping of Team Cymru.

During incident handling, we were lacking an historical view of IP address announcement evolution over time. It is not uncommon to have IP addresses announced by different BGP AS number over a period of time. We developed a service, freely accessible to the whole community, to look up IP addresses announcements in the past. Currently, the service covers a time span of more than 4 years until today.

How to use the service?

Please have a look at the documentation of the project.

HTTP interface

If you don’t have WHOIS access from your location, you can still access the service via a web interface.

Is the software for this service publicly available?

The software is distributed as free software. The software is available on our GitHub repository.