Tag Archives: Linux

Observing packets on the wire flying by

Posted on August 28, 2016 by Jacco

Anyone who has ever tried to install a modem or configure an Internet connection has almost certainly wondered if there’s any traffic flowing back and forth from networks. Observing network traffic that is generated by a PC or Mac is … Continue reading →

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Javascript IPsec configuration generator for site-2-site VPN gateways

Posted on August 28, 2015 by Jacco

Today, access to the internet is practically everywhere. Private communication across it is often taken for granted. There is an entire industry around secure communication and a lot of the equipment used for securing network boundaries, VPNs specifically, relies on the … Continue reading →

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Email and malware dissection, Part II

Posted on September 24, 2014 by Jacco

If you’re running a mail server on the Internet, you will surely be familiar with spam and malicious email. This post is the last part on how to identify and isolate malware in email while respecting your users’ email privacy. … Continue reading →

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Resizing multiple images

Posted on July 30, 2013 by Jacco

I’m sure there are easier ways, and better I assume, to reduce the size of multiple images at once. But there was some point in time where I couldn’t resist the urge of solving this myself using ImageMagick and Tcl/Tk. … Continue reading →

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