which algorithm is better for encrypt and decrypt data inside a project?
i designed and developed a site like below :
htttp://www.soscharge.com
this site is about mobile charge codes ...
i want to encrypt mobile charge codes during insert to database and decrypt them for showing to users...
hash algorithm is not a good idea about this purpose (one way algorithm)
i heard something about symmetric and asymmetric algorithms (but i want to learn how can i write a simple and powerfull algorithm by myself)
thanks in advance