Cryptographic hash function with a 128-bit (16-byte) hash value
Whirlpool is a cryptographic hash function designed by Rijmen and Barreto.
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
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?