Building your own MMDB databases for IP-specific data
If you use a GeoIP database, you're probably familiar with MaxMind's MMDB format.
At MaxMind, we created the MMDB format because we needed a format that was very fast and highly portable. MMDB comes with supported readers in many languages. In this blog post, we'll use Perl modules to create an MMDB file which contains an access list of IP addresses. This kind of database could be used when allowing access to a VPN or a hosted application.
Read the full blog post.