Methods of encryption... Cyphers...

Dave!

Is cypher not the coolest word ever? Okay it's not...

Anywho,

I was watching 'the Prestige' tonight, and they make a big deal of the fact that Christian Bale uses a keyword cypher in his diary. I had a quick look on wikipedia and it so happens to have an entry for this!
http://en.wikipedia.org/wiki/Keyword_cipher

The basic idea is that you think of a keyword, say 'CYPHER', and you take each of its letters out of the alphabet and put them at the start... .hard to explain, but this is an example:

A B C D E F G H I J K L M N O P Q R S T U V W X Y Z
becomes...
C Y P H E R A B D F G I J K L M N O Q S T U V W X Z

And then when you're writing a message, you substitute the new letters in for the old ones...

I AM DAVE
becomes...
D CJ HCUE

And to decipher it you need the keyword! Of course there are ways around it, and more sophisticated methods, but it's still pretty cool

Anywho, if you scroll to the bottom of the wikipedia page it gives a whole bunch of methods of encryption:

Ciphers: ADFGVX | Affine | Alberti | Atbash | Autokey | Bifid | Book | Caesar | Four-square | Hill | Keyword | Nihilist | Permutation | Pigpen | Playfair | Polyalphabetic | Polybius | Rail Fence | Reihenschieber | Reservehandverfahren | ROT13 | Running key | Scytale | Smithy code | Solitaire | Straddling checkerboard | Substitution | Tap Code | Transposition | Trifid | Two-square | VIC cipher | Vigenère

I don't plan on becoming an expert at them all, cos they hurt my head, but they're still pretty interesting ... right?... RIGHT?

looksee

or u cd jst uz txt spk

Karoma

ooookaay...

looksee wrote:

or u cd jst uz txt spk

Don't be daft. It has to be possible to decode it.



Moved to blog.
If it only it were possible

Archeron

Hahahahaha! What a weird topic. I wuold encrypt this post, but then noone would understand it.



Or did I anyway?

looksee

Sheesh, are those the two fastest comments ever, or has the clock stopped

Orange69

I think a cookie is in order!

ircoha

DI cypher this then: WALOB

Capt'n Midnight

one time pads ftw

anyway after they ban encryption we will all be qh$Y0Z\g%W[sA

Dave!

What's your favourite cypher?

I may start a poll!

Karoma

Capt'n Midnight wrote: »

one time pads ftw

anyway after they ban encryption we will all be qh$Y0Z\g%W[sA

Then, we switch to steganographic techniques and blow up the House of Parliament of something. That's my understanding of how one should deal with these things. I'm willing to travel.

Karoma

DaveMcG wrote: »

What's your favourite cypher?

aha! So that's how you pull all the wimminz!!1

Orange69

Karoma wrote: »

aha! So that's how you pull all the wimminz!!1

I have actually done some compression and encryption work.. should i mention it down the disco?

Karoma

Orange69 wrote: »

I have actually done some compression and encryption work.. should i mention it down the disco?

Definitely. It'll warm them up for the political discussion - i.e. You repeatedly stating that everything is the fault of Fianna Fáil...

Jay D

God this is too much at this hour

Dave!

STOP SPAMMING MY THREAD, KAROMA!!! P*ss off!

Giblet

The thing about such a simple cypher is that will large volumes of text, they can be decoded easily by statistical analysis of the frequency and positioning of the letters.

Naos

Touchy DaveMcG, touchy....

Without Wax,

Mear

Orange69

Karoma wrote: »

Definitely. It'll warm them up for the political discussion - i.e. You repeatedly stating that everything is the fault of Fianna Fáil...

Oh i bet you are one of the sheep who voted for Bertie! lol!

Dave!

Giblet wrote: »

The thing about such a simple cypher is that will large volumes of text, they can be decoded easily by statistical analysis of the frequency and positioning of the letters.

Yeah I know. Still cool though.

leninbenjamin

I read a book about the history of codes and cyphers... man it's heavy ****. i could vaguely understand the principles behind the developments up until around just after WWII. then i had a nervous breakdown and refused to go out of my room for 6 weeks...

Orange69

leninbenjamin wrote: »

I read a book about the history of codes and cyphers... man it's heavy ****. i could vaguely understand the principles behind the developments up until around just after WWII. then i had a nervous breakdown and refused to go out of my room for 6 weeks...

Ya i did a paper about the enigma machine... Had a similar experience.

Karoma

Giblet wrote: »

The thing about such a simple cypher is that will large volumes of text, they can be decoded easily by statistical analysis of the frequency and positioning of the letters.

Naq fbzr bs gur bguref yvfgrq qb abg rira erdhver gung zhpu rssbeg.

Archeron

DaveMcG wrote: »

Yeah I know. Still cool though.

But there are so many ways to create cyphers that if we wished, we could live in a word of total utter confusion. Lets try only to confuse each other during converations debating the value of drugs and hookers.
That way we all are at least relatively happy.

leninbenjamin

Karoma wrote: »

Naq fbzr bs gur bguref yvfgrq qb abg rira erdhver gung zhpu rssbeg.

i was waiting for someone to do that.

Karoma wrote:

AND SOME OF THE OTHERS LISTED DO NOT EVEN REQUIRE THAT MUCH EFFORT

Blowfish

DaveMcG wrote: »

What's your favourite cypher?

<

---

It's a block cipher rather than a keyword one, but I was setting up my OpenBSD box at the time I signed up here, so on a whim decided to use it as my username.

ZorbaTehZ

How about trying to decipher YORE MA.

Terry

A=1
b=2
c=3

Capt'n Midnight

Orange69 wrote: »

Ya i did a paper about the enigma machine... Had a similar experience.

Always amazed at how little you hear about the Poles who cracked it. Instead you hear all about is the derivative work done later.

Black Swan

Giblet wrote: »

The thing about such a simple cypher is that will large volumes of text, they can be decoded easily by statistical analysis of the frequency and positioning of the letters.

Especially with "E" being the most frequently occurring letter in English, with others having a probability that is known by code crackers (and their specialised software).

One time pads are the way to go!

Karoma

http://xkcd.com/177/

Giblet

Karoma wrote: »

Naq fbzr bs gur bguref yvfgrq qb abg rira erdhver gung zhpu rssbeg.

Good ol' ROT13

AlmightyCushion

Just use 1337 speak. Only the 1337 will be able to decipher what you are saying then.

Jesus Wept

IF YOU ARE READING THIS, YOU ARE A FANTASTIC CODE BREAKER.

Earthhorse

There's a good book by Simon Singh on this called, imaginatively enough, The Code Book. You should pick it up if this subject interests you.

Terry wrote: »

A=1
b=2
c=3

Way to give away our state secrets Terry.

Tar.Aldarion

Just use varying keywords.

Karoma

Giblet wrote: »

Good ol' ROT13

Before there were [noparse]

[/noparse] tags. Kids these days have to use tools to convert to/from ROT13. I BLAME THE POOR EDUMACATION SYSTEM ON BERTIE!!1!

Terry

Do a thing without using "E".

Difficult to sort out.

Blowfish

Terry wrote: »

Do a thing without using "E".

Difficult to sort out.

It's deinitely possible though.

Giblet

You'd easily get the o's then the t, the the u, in your example.

Terry

Giblet wrote: »

You'd easily get the o's then the t, the the u, in your example.

txt spk it is then.

Indechipherable by any adult.

Giblet

You win.

Voodu Child

Write your message in Irish, nobody will be able to understand it then. Except maybe a few beardies in Connemara.

The yanks did something similar with the Navajo Codetalkers, although im sure Irish is much more indecipherable.

Mr. CooL ICE

@TheRigger - Legend


I am doing encryption for my final year project so I know more than I could really care about. I had a presentation a few weeks ago about it and my nerves were really killing me beforehand, so I decided to bombard the presentation panel with as much jargon as possible so they wouldn't ask any questions. They were all academics and lecturers, so they were afraid to show that they had no idea what I was talking about, so all went quite well

Naikon

voodoo_child wrote: »

Write your message in Irish, nobody will be able to understand it then. Except maybe a few beardies in Connemara.

The yanks did something similar with the Navajo Codetalkers, although im sure Irish is much more indecipherable.

LOL