Archive for March, 2010

CIDR Zone file merging for higher performance

March 21st, 2010 6 comments

UPDATE: AUGUST 15th, 2014. IPv4 country aggregated IP address blocks are now offered for free downloads. Read our official blog post about aggregated IP address blocks and enjoy!

We got an email from person suggesting us to use CIDR zone file merging script from We have ran a few in-house tests and this Perl based script effectively decreases CIDR IP block count up to 60% or even more.

The less firewall rules you have set-up in your packet filter (server or firewall) the less matching needs to be done – this effectively decreases load and usage. In the next upcoming week we will fully implement this feature into freely available country zone files.

Thank you for your continued support and feel free to send us more suggestions or recommendations!

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