Sunday, October 30, 2005

word verification

I've recently turned on word verification because I got one piece of spam e-mail. I'm kind of regretting it because I tried to post a response on my own blog tonight and the whirly whirly word verification made me feel a bit ill. It was also quite hard to read which had nothing to do with the enormous Laphroig I had just consumed.

Saturday, October 29, 2005

Installation Art

My Dad has bought a new whizzy PC with a 3GHz P4 and 1Gb RAM (still not as good as the PowerMac I have on order). This has left him with a spare PC not doing anything but coincidentally his old PC was infested with some internet worm. So the plan was to reinstall Windows (I'd rather he used Linux, but never mind) thus wiping said worm into oblivion.

The first problem was that the install CD was WinXP and the computer obviously already has SP2 on it so you can't run setup from within Windows. You also can't reformat the disk because Windows is using it. So I decided to boot from the CD and do a new install.

I stuck the CD in the drive and rebooted. The PC took this completely in its stride and went straight into Windows XP - curses. I rebooted again and checked the BIOS settings. Aha, the computer was configured to boot from disk before CD ROM. I changed the settings around and rebooted. The PC took this completely in its stride and went straight into Windows XP. After trying this several times, I disabled booting from disk completely and rebooted. The computer asked me to put a proper disk in drive A, I pressed escape and it told me to "press any key to boot from CD". While I was looking for the "any" key (ha ha), it decided I was too slow and went straight into Windows XP.

The next time I was ready for it and got it to boot from the CD. I immediately deleted the NTFS partitions to keep that pesky operating system down (that'll fix it good) and I'm now installing a pristine copy of Windows XP.

Further updates as they happen.

Update


Disappointingly the installation process went very smoothly. It took a little while to get all the patches and SP2 on. The only hitch was doing the video card update. for some reason the computer thought it only knew 640x480 16 colour mode.

Thursday, October 27, 2005

Visual Studio

This article should be read by anybody who aspires to writing applications for the .Net environment. It never occurred to me before that it is even possible to write a Windows Forms app from scratch without using the inbuilt VS.Net wizards.

As a professional programmer, I can tell you that VS.Net is one of the best - if not the best - programming tools there is. However, it encourages amateurs to think that programming is easy and anybody can write an application (which they can given a tool like VS.Net or, even more dangerously, Microsoft Access, just not a good one). Unfortunately, for any real useful app, there really is more to it than dragging a few controls onto a form. If I had a pound for every time I've gone to a customer and had to sort out a system that was written in Access or Excel with VBA and is simply not up to the job because the code is unmaintainable or it doesn't work when three people are using it at the same time, I'd have £17 or thereabouts.

Link

Wednesday, October 26, 2005

New Toy

For my current project, I need a dual processor Macintosh. When I say "need" I really do actually need because I have to test my device driver on multi processor kernels. It's a trial, I know. So I've just put my order in for a twin core G5 Powermac - yum.

I don't really know what I'll use it for after the project's over though - Warcraft 3 maybe.

Saturday, October 22, 2005

Don't panic Captain Mainwaring

What is it with this bird flu? A parrot with it gets found out in quarantine and the whole media is going beserk. The infected bird was caught by the measure designed to catch it. What is the problem?

This is another case where the media is working up a story just so that they can have a story. Bah humbug!

Wednesday, October 19, 2005

Did the Earth move for you?

I got to the hotel at around 1pm. My room was on the 6th floor. I was pretty tired, so I decided to stop in my room for the rest of the day. So I lay on my bed watching the Chinese Grand Prix and suddenly I got this bizarre sensation that the room was moving. I'm tired, I thought, it's that whirley sensation you sometimes get after coming off a long flight, perhaps as a result of deep vein thrombosis.

Then I realised the bed actually was moving. Perhaps, this was some Japanese mechanical automatic rocking bed and I had inadvertantly switched it on. Then I realised other things in the room were moving back and forth and in fact the whole room was moving back and forth. This carried on for about a minute during which the hotel completely failed to collapse, so I went back to watching the Grand Prix.

That's how I survived my first earthquake.

Tokyo

This message comes to you from Japan where I am in the airport internet lounge awaiting my flight home.

I've just finished a 3 day whirlwind tour of a hotel and the Memory Tech office and several restaurants. As I have limited time for my 100 yen, I'll save most of the stuff I'm going to write until later.

Suffice it to say, the earthquake was the highlight.

Sunday, October 09, 2005

Diving in to challenge 4

The fourth challenge, the Vigenere cipher was pretty straight forward to solve. Using Singh's (well Babbage's) method on character sequences of four and five letters, I figured out the key length fairly quickly. Then, a frequency analysis of each group of letters encoded by the same key letter revealed the letter "E" in each case and from there I quckly worked out the key.

Probably the most time consuming part was writing the Vigenere decoder.

Que?

Ha! Well I figured out "q" pretty easily and from there cipher 3 fell. Well, actually, I haven't got all of it but the important keyword dropped out pretty quickly.

I expect cipher 4 will be quite easy if I follow the rules given in Somon Singh's book. My betting (before I even start) is that it is written in French.

Saturday, October 08, 2005

Cracking cheese Grommit

I'm making a bit of a leap in my code cracking challenge. I've decided to assume for the moment that text 3 is in Italian. Google says that Italian has five letters that are not used (JKWXY). This would fit nicely with a cipher alphabet in which all of the vowels have two cipher text equivalents. Italian also fits nicely in that virtually all words end in vowels or an "L". This fits with my digraph analysis of the cipher text.

Wednesday, October 05, 2005

Milk Monster's Mum said...

In response to my last blog MMM said

You're not making the dangerous assumption that there's a one to one mapping between plaintext and cipher are you?

so I thought I'd better explain some of my reasoning for being where I am.

In the book we are given the clue that the cipher is monoalphabetic with homophones which means that several symbols in the cipher text mean one letter. This is usually done to disguise the frequency count.

I started off with the assumption that each digraph (two letter sequence) represents a plaintext letter, there would be several digraphs representing each of the more common letters. However, this doesn't really make sense otherwise why would we need the asterisk character?

Doing a frequency count reveals there are far too many 'X's particularly for a cipher where the frequency count is disguised so X must be special in some way. I thought at first it could be some sort of extension character so that all the letters represented some plain text letter except when there was an X it would be X and the next letter or the previous letter and X. However, that still begs the question: why do you need an asterisk? so my current theory is that X is a space which is kind of born out by the fact that X can come before virtually anything but only after a select few. Some languages have a fairly limited number of word endings.

The homophones could be provided by using a language which doesn't use the whole alphabet: e.g. you'll never see a "k" in French.

Tuesday, October 04, 2005

Crackers

I'm rereading the Code Book now and attempting the Cipher Challenge. I know the competition is over, but that's a good thing because I can crib the answers if I get stuck.

So far, I've cracked the first two, the monoalphabetic and the Caesar shift and I'm on number 3 whixh is proving tricky. Does anybody know of a language where all the words end in the same letter? or the same small subset of letters?

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