What is 128-bit Encrpytion?

[Dre]

I'm writing a paper and need some help.

In brief and simple terms, why is 128-bit encryption secure?

For example:
It's hard to crack because you need 128 characters?


Thanks in advance.

 

[stebesplace]

Question:
What is the difference between 128-bit and 40-bit encryption?

Answer:

The main difference is that 128-bit encryption provides a significantly greater amount of cryptographic protection than 40-bit encryption. With the increasing computing power of potential criminals, it is becoming more necessary to employ larger keys, as evidenced by a recent study by several leading cryptographers.

In terms of what the numbers represent, "128" and "40" bit encryption refer to the size of the key used to encrypt the message. Roughly speaking, 128-bit encryption is 309,485,009,821,345,068,724,781,056 times stronger than 40-bit encryption. Presently, 40-bit encryption is not considered "strong" security in the cryptographic community. However, even taking into account Moore's Law, which states that computing power doubles about every 18 months, 128-bit encryption represents a very strong method of encryption for the forseeable future.

 

[notfred]

a character is not 1 bit.

 

[stebesplace]

Require 8.77 x 1017 years to crack 128-bit encryption
A 128-bit key size has 2128 or around 3.4 x 1038 possible combination. Even if you have the world best super computer, ASCI White, SP Power3 375 MHz manufactured by IBM as of November 2000, it would take 8.77 x 1017years to test all combinations.
Assuming your have the super computer, ASCI White, SP Power3 375 MHz has 8192 processors which totals a capability of 12.3 teraflops (trillions of operations/second), available to you. Also it just needs one computer operation to test a possible combination (which is already faster than what it can do). To use brute force attack (checking all combinations) on this encryption algorithm. It would take

3.4 x 1038
-------------- seconds ~ 2.76 x 1025sec
12.3 x 1012
i.e. 876530835323573935 years or 8.77 x 1017 years

to successfully try all combinations. Let alone ASCI White cannot process as fast as what described here. You can be sure that your data stored on our server is 100% secured.

 

[Dre]

Thanks guys. That's all I needed.

 

[Nothinman]

Require 8.77 x 1017 years to crack 128-bit encryption

Assuming the last key tried is the right key. I could get lucky and get it right the first try.

Let alone ASCI White cannot process as fast as what described here. You can be sure that your data stored on our server is 100% secured.

You're data is never 100% sure, you'd be a fool to believe that no matter how big the encryption key you used is.