Monday, June 8, 2015

Asymmetrical Cryptography...Falling Down The Trapdoor



Asymmetrical Cryptography...Falling Down The Trapdoor


Asymmetrical encryption relies on trapdoors: math problems that are easy to solve one way, but not the other. For example: 3+7.

Easy, that's 10 right? Right!

Congratulations, you just encrypted your secret message. Now the hard part is reversing it if you're a hacker.

The bad guy knows your answer is 10, and they know it is the sum of two numbers:

1+9=10?
2+8=10?
3+7=10
4+6=10
5+5=10
0.2+9.8=10?
3.6+5.4=10?
Etc.

Hmmm...even if you find the two numbers that solve the puzzle, you're not sure which set of two numbers (3 and 7) are the ones needed for the code. The idea is simple though. In our case we got it on the third try.

Okay, my new number is the sum of two numbers. I'll hide the first part and you play the hacker. What two numbers did I add to get 1,430,286,731,292?

Same exact principal and method, but now almost impossible to solve. Falling down a trapdoor is easy-being y back out is the hard part.

By the way, the solution to my last code:

1,430,286,731,292 =  2.1   +  1,430,286,731,288.9 



Did you guess it?

If you did guess it next time I'll multiply the numbers instead of adding them, or maybe divide them into each other three times then multiply by 2.345, etc.

But now you know what a trapdoor is in cryptography.



1973=meow