operation of a hash table. suggested the use of crypto puzzles [9] to force clients to perform more work before the server does its work. Provably requiring the client to con- sume CPU time may make sense for fundamen- tally expensive operations like RSA decryption, but it seems out of place when the expensive opera- tion (e.g., HTML table layout) is only expensive because a poor algorithm was used in the system. Another recent paper [16] is a toolkit that allows programmers to inject sensors and actuators into a program. When a resource abuse is detected an ap- propriate action is taken. Bucket 0 1 2 3 4 5 Figure 2: Worst-case hash table collisions. bles are so common that programming languages like Perl provide syntactic sugar to represent hash tables as “associative arrays,” making them easy for programmers to use. Programmers clearly prefer hash tables for their constant-time expected behav- ior, despite their worst-case O(n) per-operation run- ning time. After all, what are the odds that a hash table will degenerate to its worst case behavior? In typical usage, objects to be inserted into a hashtable are first reduced to a 32-bit hash value. Strings might be hashed using a checksum oper- Craft input for collision
comprised entirely of lowercase characters 3.36% were found in a common password dictionary 4.67% were reused by the same person on a totally unrelated service (Gawker) 5.Only 1% of them contained a non-alphanumeric character 77 million breached PlayStation Network accounts
Vector (IV) is provided along with the key when starting an encrypt or decrypt operation. If CBC mode is selected and no IV is provided, an IV of all zeroes will be used.