Hi All,

You've found the blog of Leighly G Penrod (better known as Lee Penrod). Over the years I've helped thousands of people with technology questions. I started this blog to share some of the problems I've personally solved, and to act as a place to put bits of new articles before they are ready for release.

In the past I wrote serveral things published by I worked for them for several years including doing various bits of technical writing. Although I no longer work for them, I do still put up some content on my blog now and then.

If you are not familiar with my prior work, feel free to see these popular guides I have written-

How to Install Front USB 3.0 Connections

How to Install Front USB
(connecting front ports to the motherboard)

Understanding System Memory and CPU speeds:
A layman's guide to the Front Side Bus (FSB)

Hooking up a Neon Light
[Old Article on making a card neon from Walmart work in a PC]

Tuesday, October 30, 2012

A few quick links related to IP checking

Every now and then a Subnet calculator is handy, especially if you are managing IP Block lists.  Here are a few useful links and projects I have found to be helpful.

1) PHP Subnet Calculator @ Sourceforge. A simple open source subnet calculator written in PHP. The author has a example site that is great if you need to do a simple calc from slash notation.

2) Lexdos. A simple site that shows an arbitrary IP address vs a Google Map.

3) Pear Package: Net_GeoIP.  This handy little package will give you the ability to turn an IP address into a city / country / region and give you a rough guess on LAT/LONG.  It does depend on a source data file put out by MaxMind but the basic version ( GeoCity Lite ) is free. The pear package + GeoCity Lite is enough to at least tell if an incoming request is from a different country -- potentially very useful for fraud detection.


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