
 Various statistics for generating an RSA Public-Private key pair ,encrypting an arbitrary message using the public key and decrypting the
 message using the private key.

 The table below shows the time for above operations as a function of key size :
 Message Size = 250 bytes
                                                       TIME in milliseconds
                     **************************************************************************************
       KEY SIZE          Public-Private key generation        Encryption             Decryption 
         128                          142                       489                    485
         256                          312                       3089                   3107
         512                          1054                      22212                  22732
         768                          2316                      70360                  72163         
         1024                         5380                      168559                 167139

     CONCLUSION : As the key size increases time for key generation, encryption and decryption increases. As the key size is doubled,
                  the increase in time for above operation is more than twice.

 The table below shows the time for encrypting and decrypting various size messages for two key sizes :

     KEY SIZE = 32 bits
                                                             TIME in milliseconds
                                           **************************************************************
                Message Size in bytes               Time for encryption             Time for decryption
                   250                                     58                                41
                   500                                     104                               49
                   750                                     126                               79
                   1000                                    146                               90    
                   2500                                    317                               198
                   4000                                    461                               318 

     KEY SIZE = 64 bits

                Message Size in bytes               Time for encryption             Time for decryption
                    250                                    149                                123
                    500                                    219                                191
                    750                                    322                                349
                    1000                                   422                                395
                    2500                                   1031                               935
                    4000                                   1604                               1510

    CONCLUSION : Increase in message size increases the time for both encryption and decryption. this time also increases as key size 
                 increases.

 The table below shows the time for Public-Private key generation for various values of "probability of P, Q being prime" variable in the 
 constructor of the BigInteger class :
            
            Probability  = 1 - 1/power(2,certainity)
            KEY SIZE =32 bits
                                                      
   Certainity of P and Q being prime              Time in milliseconds for Public-Private key generation                                                        5                                                11
                  10                                                22
                  15                                                23
                  20                                                31
                  25                                                38
                  30                                                39
                  50                                                50    
    CONCLUSION : Probability increases with certainity. As the probability of P and q being prime increases , time for key generation 
                 increases. The increase in time is due to increase in time for searching two prime numbers P and Q with the given 
                 probability.
