Wednesday, 4 August 2010

Cryptic Crush


T'other half is really into cryptography, so for his birthday I'm doing him a message in a bottle that I've coded for him to break. At least that was the plan - in which I have rather failed by making it into something that doesn't actually fit into a bottle. I'm going to wrap it around a bottle instead - this method of presentation having the advantage that then the bottle can still contain rum (Which in itself has the advantage that it will necessitate a rum-tasting trip, since Sailor Jerry have 'improved' their recipe and now we don't have a favourite rum anymore.)

Coded Up
Right - the word I've coded is 'Mush' (it's one of those heinous relationship jokes that no one but the two of us gets. sorry.) chosen as it's short and simple (to begin with. It got longer, because of the way I treated it - in fact, it turned out it got alot longer - which is why my message no longer fits into a bottle!)

First stage is simple - put it into binary, which I then translate into written numbers. Then I put it through an alphabet substitution cypher (A Caesar cipher), which shifts between each letter of the original word. Which is translated into Morse code.

M = 01001101
o ten o eleven o one
t yjs t jqjajs t tsj (shifts by 5)
- / -.-- .--- ... / - / .--- --.- .--- .- .--- ... / - / - ... .---

U = 01010101
four bracket zero one bracket
pyeb lbkmuod joby yxo lbkmuod (shifts by 10)
.--. -.-- . -... / .-.. -... -.- -- ..- --- -.. / .--- --- -... -.-- / -.-- -..- --- / .-.. -... -.- -- ..- --- -..

S =  01010011
zero one zero one double zero double one
otgd dct otgd dct sdjqat otgd sdjqat dct (shifts by 15)
--- - --. -.. / -.. -.-. - / --- - --. -.. / -.. -.-. - / ... -.. .--- --.- .- - / --- - --. -.. / ... -.. .--- --.- .- - / -.. -.-. -

H = 01001000
nought one hundred one thousand
hioabn ihy bohxlyx ihy nbiomuhx (shifts by 20)
.... .. --- .- -... -. / .. .... -.-- / -... --- .... -..- .-.. -.-- -..- / .. .... -.-- / -. -... .. --- -- ..- .... -..-

So, to progress from here, the Morse code gets translated into text (dash dot long dash dit short dah dot....), and from there into Elian Script (which is basically a prettified pigpen cipher)
At which point I had to work out how to present this so that Wolf will know where each new letter begins, and each new word... so I threw in a colour element. Basically, each letter of the Morse Code is written in a different colour, and each word will be written in distinctly separate blocks.
And that is, essentially, the finished code! Hurrah.

At this point I have to give a massive shout-out thank you to Aimee & Dot for carefully checking over my work for mistakes - I really appreciate the time you took to help me out.
I confess I'm a little concerned that each step is very simple, and Wolf will break the back of it almost instantly. The only difficulty he may encounter being the  large amounts of repetition throwing off alot of standard key-finding methods (eg, frequency attacks are  unlikely to be very useful). Had I come up with this idea a little further in advance of his Birthday, I may of been able to do some research and create something a little more interesting - but I'm hoping he will appreciate that cryptography is his bag, not mine, and it's the gesture that counts and all that happy clappy what-not...
And it's just ironic that the day I completed the neat write up of the code I started reading Popco by Scarlett Thomas, (excellent read so far, fyi) which has inspired lots of much more interesting and challenging ideas inside my head... but I guess they'll have to wait for next year...


And the Pretty girlie stuff
So, now all that was left to do was write the bugger up. 
I managed to stumble upon a 'Complete Illustrated Works of Lewis Carroll' in a charity shop, which seemed an appropriate starting point given that  Carroll was also a math nerd and liked a bit of cryptanalysis himslf, plus Wolf has been known to call me 'his Alice' (More rom-com awful in-jokes. So sorry) . I brought the book and immediatly proceeded to rip apart. Being somewhat of a book-lover (slight understatement possibly?) this caused me actual physical pain, on the level that I felt each little tear like it was going into my own skin... 
To cure this, I decided that I should apply the restorative benefits of tea, not only to myself (in the form of mug), but also to the torn out pages (in the form of bath) - having the added effect of nicely aging the horrible cheap white paper that the book had been printed on. Because if there's one thing a degree in Stage Management teaches you, it's how to tea-stain stuff really nicely. Thanks Guildhall.

Having tea-stained enough pages, I ironed them (so they sit nicer together, And wrote up the code 'in neat.' I used ABT pens by Tombow, because they are available in a good colour range, but I found the brush end (They are duel ended, with a brush end and a thin-tip end) got knackered pretty quickly, even though I wasn't exactly hard-wearing on them - a bit disappointing given the fairly high individual cost of the pens.
Once it was written up and I'd checked over my work (again. Just to be sure...) it was time to bind the pages together. Now, i know exactly zero about bookbinding, and I basically made it up as i went along, but it seemed to come out pretty well. I used a ladder stitch to sew them pages together, then just glued (Brushable superglue again. I'm still in love with this stuff) a length of wide satin ribbon over the stitches. Then, purely for decorative effect and added Wolf-ness, I finished it off by popping a Skull-head rivet (the kind meant for leather working) through the spine. I decided to 'soften' the edges, the easiest way to do which being to carry it around in my handbag for a couple of days - just to slightly batter the pages and give the book as a whole more of a naturally aged look. And.... done.
I shall report back on boy's reaction (and the total number of minutes it takes him to decipher) post birthday celebrations
Post-birthday write up here 

4 comments:

  1. Wonderful! I absolutely love The Mouse's Tale!

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  2. Oh and if you need a favorite rum, I highly recommend Appleton Estate. It's amazing, we even visited the distillery.
    Also, check out the Morse code hat (http://charliesweblog.blogspot.com/2008/10/faster-than-speeding-bullet-morse-code.html)made for my sis's boyfriend, I haven't tried binary yet, but may have to in the future.

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  3. Yhea, i saw the hat when you first made it - such a clever idea!
    Loving the rum suggestion - Might pick upo a bottle to try next weekend, thankyou xx

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