IPNetDB is a database of routing information for the internet. It's updated weekly and compressed into the popular mmdb-format database files with existing libraries in most languages.<p>The primary use would be to answer questions like what ISP an IP address belongs to, what publicly routed CIDR an IP address is part of or what prefixes are broadcasted by an ASN. You could use it to handle traffic from an ISP differently, prioritize some ISPs, use the allocation country information to route traffic from different countries internally, expand IP based filtering to entire CIDRs or networks or any other query that requires information on what network is advertising what IP addresses.<p>Allocation, advertisement and peering information is up to date weekly. Entity information is slowly updated over a period of a month or two.<p>It's free for open source and non-commercial use and small enough to embed into most applications.