Just a real quick snippet today. If you followed along my first Arduino post (Getting started with Arduino) then you should already have a simple blinking LED on Pin 10 (or pin of your choice). I wanted to take that just a step further and use PWM (Pulse Width Modulation) for a fade in / fade out effect.
PWM uses a pulsing digital signal (high/low) to simulate the effect of an analog signal. If you really want to learn the technical details of PWM, head on over to the Arduino page – http://arduino.cc/en/Tutorial/PWM
This is going to be a short and sweet post, but it touches on something I had to deal with just the other day.
I was going through my router, which I do on a regular basis, to check what unknown network devices were showing up in the network list. In my case I usually do this for two reasons. The first is to name all my devices in the router itself and typically assign it a static IP. The second is for pure security. I want to know what devices are on my network, and who the device belongs to.
The particular unknown network device that I noticed, and could not identify was named “GainSpand48cb6“. I usually take pride in naming my devices, so GainSpan was not something that I had setup. I made the assumption that the d48cb6 was the last 6 digits in the mac address, which I confirmed by looking at the device info more deeply.
Well its been so beautiful outside here lately *sarcasm alert* (averaging -40 degrees Celsius…) I decided now might be a good time to dust off my Arduino boards.
First off, if you have any experience with Arduino micro controllers, this post probably wont be for you. Its been many… many years since I have done any work with them (ahem… high school). I need to build my own skill set back up, so this is a recap for myself, and for those who might be just starting out (or looking to start out) with Arduino boards.
There comes a time in every security professionals career where either an installer code was lost, changed, locked out, or forgotten.
An installer code is a 4 digit code that, when entered into the keypad, will allow you into the programming menus of an alarm panel.
Some panels however have back doors hidden in them that allow access to the installer menu without ever knowing the code. Take the Honeywell Lynx Touch L5100 for example.
This beauty is actually one of my favorite alarm panels to work with (only being beaten by the Lynx Touch L7000 of course) combining a whole hefty set of features such as Z-Wave, Wifi, and GSM into a small easy to install package.
Quick tip for those of you using AVG Firewall. I ran into an issue where, after installing AVG, my VMWare virtual machine would not longer connect to the internet. Windows still showed a connection and I could still ping (both by IP and domain names), but when I open a browser to load a web page, nothing happened.
At first I didn’t realize it was AVG that was causing the issue (it’s been a while since I last used my VM so I didnt make the connection right away). But some simple troubleshooting narrowed it down (set firewall to “Allow All“) and boom, internet started working right away.
As some of you may (or may not) know, by default apache2 allows something called “Directory Listing”. Essentially what this means is that when you visit your web server, if you browse to a directory within your www folder that does not contain an index page (index.php, index.htm, index.html, etc.), apache2 will actually spit out (or list) the entire contents of that folder. This should be a concern for anyone running a production server, and unless there is a specific need for directory listing its always a good idea to disable it. There is tonnes of different opinions on whether or not its a security issue to leave it enabled, and to this I have to say to each their own. Personally I feel it is a security risk, but at best disabling it is simply security by obscurity.
Here’s a quick little tip to get your week started.
Remember back in the Windows 7 days (oh so long ago…) when all you had to do to change the network name was click on the icon in the “Network and Sharing Center” and it would let you change the network name as well as the icon?
What? You don’t remember? Okay okay, so granted this wasn’t a widely used feature by any means, but sometimes (especially if you’re in any sort of tech industry) its nice to name your networks.
Something as simple as describing how to change a PC to a static IP address (or back to a dynamic IP address ) is often overlooked by people who have been in the industry for a long time. I’m guilty myself of this. Too often while providing phone support (either internal or to customers) I will throw out “Oh yeah I just need you to set your computers IP address statically”. Most of the time I bet that I probably get a very evil glare on the other side of the phone.
You might be asking right now why you would ever need this information, and to be perfectly blunt most people will never need this information. However, if you ever have to phone support for any device that connects to the internet, believe me, the tech on the other line will praise you for knowing a little of the basics.
If you’re a newcomer into the Android world and want to start your adventure into Android development, you wont get very far without first setting up the Android SDK.
It can seem overwhelming setting up the Android SDK for the first time, but it’s actually pretty straight forward.
First things first, its important to note that I will be covering this on a Windows based PC. Depending on your configuration the instructions may be slightly different but they should be similar enough to work your way through it. I’m not here to start a debate, I use both Linux and Windows, but my preferred development environment when it comes to Android is Windows.
It happens to all I.T. guys sooner or later. You have a device on a network (maybe yours, or maybe a customers) and you need to figure out what IP address that device has. Some devices will provide this information via a console port, or maybe you can check your DHCP server’s reservation list… but what if you do not have access to any of these methods?