Saturday, April 26, 2008

I've failed the Turing Test

Finally, I can see the end of my M.Sc in computer science. Almost all exams are over, and only the final project is to be completed. My projects advances kinda slow lately, but I hope things would get better. The topic of my project is spam (as in email-spam) and mechanisms to fight it. It is partially research, and partially technical. In order to test different web-mail vendors' spam filtering mechanisms, I've created free accounts at GMail, Yahoo! and Hotmail. Each of these vendors use the CAPTCHA anti-bot mechanism, so their services cannot be easily exploited. I've seen many of these CAPTCHA images before, and answered them correctly without a problem. And then came Yahoo!. According to them, I'm probably not human, as I failed the Turing Test three times, before I eventually managed to guess what's in the image, and pass the registration process. They had, by far, the worst looking CAPTCHA images.
I have a test of my own for computer software. My test tells if some software is usable or not. I call it "My Mom's Test". The test is quite simple: my mom is trying to use some software, with less than 1 minute training (zero is better). If she succeeds - the software is usable for everybody. If she doesn't - that's trash, and I remove it from her PC. Skype, for example, passed that test. The same test applies for web sites. Some sites are easy for her to use, while other sites frustrates her. For example, Google's search page is easy. Yahoo!'s registration process would fail "My Mom's Test" over and over again, as she would call me a hundred times before we can together "break" it's anti-bot and anti-human defense mechanisms. Therefor, it's unusable for my mom, and probably many other normal people. Too bad for them, as the profit from free services (such as web mail) comes from advertisement, which would bring more money if my mom would use it (she clicks ads).

Thursday, April 24, 2008

The smell of something new

You know when buy something which comes wrapped, and you tear the wrappings off, there's a nice smell of something new. Well, I got to smell that two days ago. I bought a new PC. This is the spec:
  • E8400 CPU (Dual Core, 3GHz)
  • Asus motherboard, based on Intel's G35 chipset
  • 2 Gigs RAM (800 MHz)
  • Western Digital 320GB HD (SATA 2, 16MB cache)
  • Nidia 8800GT based graphics card
  • The rest of the stuff you put in a PC
  • 20" LCD
Now I can play The Witcher, NWN2 and other games using their maximum settings. That's fun.
Also, installed 64bit Ubuntu 8.04. The new Ubuntu really rocks. Solid, fast and cool.
It took me some time to decide where to buy the new PC (or PC parts). After a long survey, I bought it on KSP. The decision was rather difficult for me, as I personally built my previous 2 PCs. Today I saw this post regarding Ivory (important: read the comments and follow-ups), and I'm more than glad I didn't go there. How rude can someone be, especially when your job is to give service. When my work included service-giving, it never crossed my mind to act like that.

Back to the fun part. Now I have 2 PCs, a laptop and some other WiFi enabled devices, so it was time to setup up a WiFi router. Bought an Edimax router. The setup was very easy, including WPA2 encryption (actually the encryption is AES in WPA2). The firewall and NAT were a bit tricky, but 10 more minutes and all was up and running. Now I have gazillion devices that all require electric power in the same room, so it's time to buy a little power-plant.

Sunday, April 13, 2008


Today I had an exam in communication security (SSL, IP-Sec, Crypto Hash, etc.). The exams are the main reason I hadn't blogged in a while. But excuses aside.
One of the questions was about how a CA signs some certificate (attribute certificate), and includes the validation key of Alice (so Bob can be sure that Alice really signed the data in the certificate). Anyhow, the lecturer, who wrote the exam, had a mistake. He wrote A.s which means Alice's signature key (private), while he meant to write A.v which means Alice's validation key (public). So, when our lecturer found out about the mistake, he wrote to the board "Q2 s/A.s/A.v/". I don't know how many students appreciated the little joke during the exam (did I mention it was difficult?), but I'm sure it made me smile.