Wednesday, 30 April 2014

Birthday Attack user manual (Release date 30 April 2014)

Birthday Attack
Manual version: 30 April 2014
  • Background
Birthday attacks are a class of brute-force techniques used in an attempt to solve a class of cryptographic hash function problems. These methods take advantage of functions which, when supplied with a random input, return one of k equally likely values. By repeatedly evaluating the function for different inputs, the same output is expected to be obtained after about1.2sqrt(k) evaluations.

more information
  • Target
Birthday attack function give user two choices:
  1. Input the desired test times and the hash value bits to calculator the probability of random hash collision will appeared.
  2. Input the desired probability of random hash collision and the hash value bits to calculator the around times need to be tested.
And can store the several times of the result data for comparing the results by user themselves.
  • UI introduction

There are three main parts of birthday attack UI.

  1. Configuration

Use for get the data of desired test times or the data of desired probability of random hash collision.


Input desired test times.
The scope of desired test times is between 1 and 10000000000000000000.


Input desired probability of random hash collision.
The scope of desired probability of random hash collision is between 0 and 100.

 2. Hash bits input

There are two methods to input hash bits.

 a. Choose a hash function and the system will get its bits automatic.




System will provide two hash function MD5 and SHA-1, or the user can choose other hash function himself.

 b. Input the bits directly


The scope of bits length is between 1 and 1000.

 3. Analysis result


These is a table to display the results for user to compare around them.

  • Buttons introduction
 1. Start


Start to generate the result. After clicked "start", the result will appear.

 2. Reset


After clicked "reset", configuration part and hash bits input part will turn back to the beginning status.

 3. Clear



After clicked "clear", the result table will become empty. All of the results showed before will disappeared.

 4. Save

After clicked any button of "Save", the result can be saved as a file.
  • Warning introduction