1. Registered User
Join Date
Jun 2001
Posts
398

## The passphrase in digi secret.

hi,

The digisecret pass phrase can accept 256 symbols
(charecters),the ascii charecters from 0-255
It would be a good idea to utilise the entire space
provided for the pass phrase,atleast *28 charecters
would be good
To generate the ascii charecter in the passphrase
use the alt+ascii-number.

If the Ascii set charecters is used an exhaustive brute
force would on a *28 charecter pass phrase would take
(if ^ denote exponent)
256^*28=*.7*76****4862**5*0772**05**078*e+*08
attempts.
A 256 charecter pass phrase take
256^255=*.262*8*04*660586222684*7487065*e+6*4
attempts if the passphrase used contains the charecter
of the ascii set.
Both are whopingly large numbers!
It would be a good idea to use a phrase longer than *28
charecters and to make use of the entir ascii set for
the pass phrase.

Regards Data.

2. Unregistered Guest

## Awesome

Wish that I was that advanced Regards, Newbietoo

3. Registered User
Join Date
Jun 2001
Posts
398
HI,

the idea behind brute force is pretty simple.

I'll try to make this simple.

Suppose ur passwd is ' z ' with out the quotes of course.

Now since a classical brute force checks for all combinations.

In english there are 26 alphabets (a-z)

So if u brute force 'z ' ,the passwd is found in 26 attempts.

Now if ur passwd is ' zz '
A complete brute force will take 26 * 26 attempts.

For an 8 alphabet word,the complete brute force takes

26*26*26....*26(8 times)

I just use ^ to represent power or exponent.

26*26*26....*26(8 times)=26^8

Now if my passwd uses both capital and small letters.

For an extensive brute force now we have to search for both capital and small letters.
If there is * alphabet in the passwd we dont know if it is capital or small letter.

So total brute force takes (26+26)=52 attempts for breaking a passwd of * charecter length.

Extending it to 8 charecters,if the passwd use both capital and small letters.

52*52*52.....*52(8 times)
which is equal to 52^8.

Here the key space is small.(A pass phrase is not a key exactly,how ever it is used to generate the keys).

For the sake of generality lets consider a pass phrase as a key.
Since there are 256 ascii charecters if u use,the difficultly of brute force increases drastically.

if ur passwd consists any * of these 256 ascii charecters,it takes 256 attempts for a complete brute force.

If u use a *28 charecter passwd ,brute force needs
256^*28 attempts

If u use a 255 charecter passwd ,(255 being the maximum input space for digisecret)brute force needs
256^255 attempts.

Regards Data.

4. Registered User
Join Date
Jun 2001
Posts
398
hi,

Hope that explanation is understood for the very reason i omitted the word permutations & combinations

Here is a thread of a c programme that illustrates the idea of a brute force.
The programme hardly does any thing but u will get the concept.

Look for subject Brute force.

I thought it was silly of me to post that,any way hope that it will be of use now :P

regards Data.