Cryptographic hash function with a 128-bit (16-byte) hash value
Whirlpool is a cryptographic hash function designed by Rijmen and Barreto.
Namely that you can use the smaller and cheap checksum to see if doing the more expensive md5 sha whirlpool is worth considering in the event of changed files;adler-32 and md5 are not comparable in this way
How reliable is the adler32 checksum?
At best it is a computationally expensive hash function like whirlpool that for example is five times slower than md5 and thus allows only a fifth of the number of hash operations in opposite to md5
PHP Session Fixation / Hijacking