/sci/ - Science & Math

>>3258801
OP IS A FAGGET

you fucked up on the o in faggot

>>3258801

Challenge accepted.

>>3258820

I didn't expect that.......

Anywho, here's a hint:

>It's a variation on the caesar shift.

I got it OP. Pretty fucking tricky... that OOC helped out a ton for the second sentence.

Won't post the answer yet if anyone else is trying it.

>>3258840

Hmmm... I'm curious.

Send the answer to my throw-away email:

rickmctroll@gmail.com

It's Caesar with the letters of the words in the second sentence reversed.

I THINK THIS JUST MIGHT WORK. LETS SEE IF ANYONE CAN FIGURE IT OUT.

First part is I THINK THIS JUST MIGHT WORK, it's a simple Caeser shift and it's shifted 23 places forward. Second part is not a Caeser shift.

>>3258847

Yeah, that's it...

So I guess it is a pretty shitty cipher.

Ok, back to the drawing board.

>>3258847
Beat me to it, well done. If I had spent more time looking at my results I would have seen that.

>>3258856
Have you considered AES?

>>3258862

No, I'm not doing this for software or anything, this is just if I want to write something down that I don't want people to read.

>>3258862
What's the strongest publically available cipher at the moment? y u no 32768 bit?

>>3258856

If you want to make a better cipher, what you need to do is have the vowels substituted for multiple different letters. For example:

The Letters X,V,B,VB, F are all the same as the vowel A.

Also, through in some symbols rather than using the letters of the Alphabet. Try using the format of the periodic table or maybe even another language to get your cipher on.

>>3258870

Hmmm... that's sum good stuff. I'm modifying it right now.

I'll definitely be using some of your advice.

>>3258875
Another obvious thing to do is to encode or drop the spaces.

But most things you can do by hand won't stop a determined adversary from reading your stuff.

What's the application? Secret diary?

>>3258900

>What's the application? Secret diary?

I'm not gonna lie. Pretty much.

Alrighty boys, here it is. I took some of your advice. This should be at just about the edge of difficulty for /sci/'s attention span.

Here you go:

MRYEPRDREVIAHEOUSCIBDLUOOHPHHESSRSUGNICKEDZZHTEMIZTESBRIHAARTZZJQWIRAEDDGNEDMOEORESERASEVNLTEENSMCES
EHTSOTHESECNECTONMPESLEXEHTITYISNEVEZZIZNECRBREAAAREDZZJQW.

Good luck!

polyalphabetic cipher!
king of ciphers!!!!!
http://en.wikipedia.org/wiki/Polyalphabetic_cipher

shit like the enigma used

Over 17% of the posts in this thread belong to OP.

>>3259054

I'm not allowed to respond to people...

And my posts are pretty obviously me, I'm not trying to trick anyone.

I could temporarily trip if that'd make you happy.

>>3259054

I'm not allowed to respond to people...?

And my posts are pretty obviously me, I'm not trying to trick anyone.

I could temporarily trip if that'd make you happy.

>>3259035

Sorry to samefag my thread, as >>3259054 so kindly pointed out.

But I figured a hint might be needed:

This one doesn't use the same shift as the first cipher.

OP, I actually work in cryptography and can give you some hints. First of all, anything you come up with is bound to be inferior to existing ciphers. You do NOT want security through obscurity. Get a tested cipher.

For your needs, you probably want to look into Playfair. It basically encrypts pairs of letters. It's like Caesar, but if Caesar had more than 600 letters.

Playfair is pretty easy to crack using a computer, but pretty hard by hand. Anybody looking at it won't be able to figure out anything. Any kind of simple substitution cipher (like it looks you're using) will fall to a variety of attacks. The simplest is just an intuitive analysis based on word length and grammar. Playfair hides that much better. Additionally, in playfair, the same letters aren't always substituted for the same thing. Here's something in playfair which you probably won't be able to crack easily.

pu lr fk sf du dv

You're very unlikely to break that without using a dictionary attack.

>>3259101

It's not just obscurity, but duly noted.

Also, show me what you got. Crack this: >>3259035

Hint number 2#:

>There is no shift at all.

(I won't self-bump anymore after this.)

>>3259035
If someone gets a hold of your diary, they'll have a huge sample of text to analyze, not just one or two sentences. Cracking that will be much easier.

>>3259187

I prefer to call it a notebook.

I don't think that would help though. I have a system where the cipher switches everyday.

Plus, just the cipher itself I think is pretty sufficient.

(saging to keep my promise)

>>3259135
Obscurity is exactly what this is. If you told us how you encrypted it, we'd know how to decrypt it. Serious cryptography is designed to be hard to break even if you know the details of the encryption algorithm. All you have to keep secret is the encryption key.

That said, I'm not sure I'd agree with the suggestion of using something well-known for this. A non-stupid person trying to break the code, having determined it's not substitution, is going to copy the text to a computer, Google online cipher breakers for several well-known simple algorithms including Playfair, and paste the text into them.

>>3259213

Hmmm.... I see.

So, if I just adapted my method to use a keyword then it would be on par with the governmental type encryption?

Honestly, I'm kinda skeptical though... I think my current cipher is doing well, and it doesn't have a keyword.

That or people just don't care and aren't trying, which I realize is very likely.

>>3259199
>I don't think that would help though.
Have you tried to break simple codes before? It helps a great deal.

> I have a system where the cipher switches everyday.
First, you're only writing two sentences or so a day? Second, unless you're memorizing a different key for each day, it will only help a little.

>>3259229
The encryption used by governments is way too laborious for you to do by hand in a reasonable amount of time.

>>3259242

Alright, I don't think anybody is really trying.

So, if anybody is trying I'll give you a minute to stop me before I give it away.

>>3259035

Alright, the answer is:

>My previous cipher sucked.
>This time things should be harder.
>I added more sentences so the complexity increased.
>Even the sentences themselves are longer.

>>3259273

And the method is fairly convoluted.

There are sentence pairs, and one sentence is written foward while the second sentence is written backward.

They are enmeshed in each other with the fibonacci sequence up to 5.

ZZ = the end of the first sentence
JQW = the end of the sentence pair

>>3259281

Also, to fill the spaces when the first sentence ended I wrote ZEBRAARBEZ repeatedly until the end of the sentence.

>>3259281
I noticed the common ZZ's but didn't know what they were. In a long sample, those ZZ's and JQW's are going to stand out very clearly, telling people where sentences begin and end, and you don't want that.

A long text also enables people to make frequency tables, which would indicate right away that you aren't changing the letters, just rearranging them.

>>3258869
AES is the industry standard, and probably best-studied symmetric key algorithm. The strongest variant defined is 256-bit, which is strong enough for any purpose.

The stream cipher RC4 is older, but very robust and easy to program, and also comes in a 256-bit key variation. I tend to find stream ciphers more versatile than block ciphers.

>>3259297

Yeah I considered adding a substitution cipher to the mix, but I figured it would be too time consuming and make something that was already hard even more ridiculously hard.