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SIP Call Process

Wireshark VoIP Challenge: Protect the Flow

The objective of my career has been pretty simple up until recently. Bad guys want information X. Keep bad guys from taking information X. Simple enough. There’s also an Appendix to that objective. Bad guys always want to take information X. Build a program to stop bad guys from taking information X. Routinely check the infrastructure […]


Wireshark VoIP Challenge

Knock off those network analysis cobwebs by downloading the file below and taking part in the Wireshark VoIP challenge. This a a short capture but a tricky one. Wireshark PCAP File MD5 Hash: 139b7dfea64ee097a4a415ba320cc5b6 The Challenge I’m currently putting together a new VoIP class and came across a nasty little Linux program that can manipulate VoIP […]


Clients React to the WiFi Pineapple

The WiFi Pineapple is a very evil rogue access point (AP) that can quite easily trick an unsuspecting WiFi enabled device or user into connecting to itself. It does this mainly through a suite of programs called PineAP. Thanks to the makers of the WiFi Pineapple, Hak5, their website is full of Get Started tutorials […]

555 Timer Monostable Mode

How to Use a 555 Timer in Monostable Mode

It’s been about a year since my last tutorial. Over the last year I learned that teaching in the real world will take away time from teaching in the virtual world. Many people have contacted me asking about a tutorial for the 555 timer in Monostable mode. The great thing about this mode is that you […]

GPS Tracker

Anatomy of a Malicious GPS Tracker

This is the kind of stuff I love. Recently I was given a GPS tracker from an individual. This tracker had been embedded in a victim’s car for 6 years. The following video examines the tracker’s components and method of install. Below the video you’ll find some close-up photos of the device. GPS Tracker Photos […]