Archive for the ‘Computer Science’ Category.

Droid Fonts

With the advent of the Android operating system for mobile devices, which was eventually purchased by Google, a family of fonts known as Droid was commissioned.

Pretty, easy to read, and free!

Pretty, easy to read, and free!

AScender Corporation’s Steve Matteson began work on them in late 2006, and my do they look nice. Although the OpenType versions (with ligatures, glyphs, and other obscure characters) cost $30 each, you can get the bog-standard TrueType ones (released under the Apache License) from here at Android’s git repository.

A good reason to hate LaTeX

It’s reading week, and there is a maths assignment to be done, with the following brief:

Please hand in printed solutions via a computer.

This is what sits in front of me as I do just that:

Who ever heard of a WYSIWYG anyway?

Who ever heard of a WYSIWYG anyway?

My brain hurts.

MarcoPolo: Context-aware computing for Mac OS X

Searching the Internet for information about OS X’s network location settings the other day yielded one of the coolest applications that I have seen in a long time: MarcoPolo.

Basically, the idea is that if you use a portable computer, you tend to use it in different contexts: At your desk at home, in the café down the road, in a university library, etc. Depending on your context, you do different things, have different settings and configurations, and use different resources.

This is where MarcoPolo steps in. By gathering information about your computer’s environment, it ‘guesses’ which context you are in. This infomation includes your current IP address, the devices you have connected, the computers surrounding you, the time of day, and even the ambient lighting conditions. When it knows where you are, it can do loads of things: mute your speakers, run a particular program, mount a particular volume, change your desktop background, to name a few.

MarcoPolo

For example: I only use my Mighty Mouse when I’m at home. If MarcoPolo detects it plugged in, it can be pretty sure that I’m at my house. Furthermore, if the ambient lighting conditions are high and I’m running off the battery, I’m probably in the garden. If I have a monitor and a power adaptor plugged in, I’m most likely at my desk. Then it can get to work: At home, I get it to mount my Mac Pro’s hard drives. When I’m not out and about I don’t need to be so paranoid, so I tell it to disable automatic logout. If I’m at my desk, I connect to my network over Ethernet, so AirPort can be turned off.

You can be really specific, right down to which room you occupy, what task you are performing, and at what time you are performing it.

Say I go to the library. MarcoPolo knows I’m there because I’m running on battery power, and I’m connected to the library’s wi-fi network. I can get it to mute the speakers so as not to disturb others and dim the screen to save power. I don’t want people hacking me, so I can set a firewall rule to block file sharing and remote login.

What’s more, it’s really expandable, because among the actions that can be triggered are shell script and AppleScript execution.

Are you getting it?

It’s really great, and free. You can get it here.

The China Channel

It is widely known that the Government of the People’s Republic of China conducts large-scale censorship of Internet access in that country. But what would it be like to actually experience, first-hand, this despicable, flawed attempt at curbing free speech?

The China Channel add-on let's you waft in and out of the great firewall of China like a cartoon ghost.

The China Channel add-on let's you waft in and out of the great firewall of China like a cartoon ghost.

That’s exactly what China Channel attempts to do. From a software point of view it’s a bit dodgy, overriding your proxy settings and reducing Firefox to a crawl, but it’s interesting nonetheless. You download the add-on from here, install it in Firefox (which takes a bit of fiddling around, as I found out), restart the browser, then you get a tasteful little icon like this above the tab bar:
Go

Clicking it points Firefox at a proxy server located somewhere inside China, behind the filters and DNS poisoning. Browsing is painfully slow, but quite surreal.

Attempting to access blocked sites gets you disconnected entirely.

Attempting to access blocked sites gets you disconnected entirely.

For example, googling ‘Tiananmen’ and visiting this BBC page about the 1989 massacre was deemed too dissenting by the powers that be, so I was blocked. One thing I hadn’t realized before is that as well as being prevented from accessing the site in question, you are also completely disconnected from the Internet for fifteen minutes. Thankfully, living in relatively liberal Ireland, I was able to just call up another proxy server and start over.

We know what you typed last summer

keyboard

Do you use something akin to the above? Isn’t the lack of wires so convenient? I thought so, at least until I read this report from remote-exploit.org, which highlights the pathetic ‘encryption’ which these systems usually employ.

Apart from some early models, which used infrared ports, the vast majority of today’s wireless keyboards runs over RF signals at various frequencies, (as well as bluetooth in some cases). It’s fast, it’s cheap, and it’s reasonably reliable, but the problem is that, like any wireless signal, it’s inherently insecure. Apparently, most wireless keyboards use very basic 8-bit encryption, and (surprise surprise) on Microsoft models, theoretically there are only 256 possible keys.

So, when you get back from PC World with your keyboard with its impressive 20-foot range, beware. Really, all that stands between your keystrokes and an attacker recording them is some sort of packet sniffer, a bit of brute force, and patience.

Telecommunications services for the 1990s

A new site kicks off with an old video. In 1969, the Post Office Research Station published this 8-minute film, showcasing its bizarre, amusing, yet often surprisingly accurate predictions about what electronic communications would be like in the 1990s. Most troubling is the ultraviolet photocopying mechanism built into the telephone terminal…