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Find and Display All Your Wi-Fi Passwords in Windows
If you have been to one of my Wireshark of Wi-Fi classes then you know I often criticize Microsoft Windows for some of its – well – inexplicable approaches to usage and security. Here is yet another example. Let’s say someone has a Rubber Ducky of some Arduino device that they want to plug into
Troubleshooting Your Network Using Port Mirroring and Packet Capture
Scenario Let’s say you have a DHCP server running on a Cisco Switch that is behaving strangely and you want to examine the traffic over a couple of hours while not creating a gigantic unmanageable capture file. A note here: I am doing this on a Cisco switch, but most all vendor switches support this
Troubleshooting The Internet Using Ping (a.k.a. ICMP)
In this article, I wanted to provide a guide to using ping – ICMP Echo – to troubleshoot your network. Most people use ping on their platform to test if they can reach a given destination. Just open up a terminal (Linux or MAC OSx) or command line (Windows: Start> Run> cmd) and enter the
BGP Autonomous System (AS) Numbers
In a recent class I was asked for some details on BGP Autonomous System (AS or ASN) Numbers. I thought I would document and provide a more complete answer here for others to learn from as well. What is the AS Number? Let’s begin with a definition. An Autonomous System Number (AS number or simply
Leveraging the Linux Logger
In this article I want to visit a “not used enough” Linux tool called logger. As with managing any system, you want to accurately annotate historical events and adding entries into the system log file is a great way to accomplish this. You can view the system log file with this command: awalding@aw-vb:~$ cat /var/log/syslog
Linux Security Focused Commands We All Need to Use
Too many people shrug off Linux for fears of security with a free and open source operating system, even today. For those of us who know that Linux is no less or more secure than any other operating system, we must be sensitive to this and we must be well versed in Linux commands that
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