The general principle of information security

Implementation of any security-related function in any project should be done according to the following principle: the system is secure if the cost of hacking it is greater than the benefits of the result of the hacking.

The amendment. And the cost of implementing such function for the developer is cheaper than the worst consequences of the disclosure of secured information.

There’s no sense in building a multi-level data protection system if the data being protected is a high scores file of a computer game (unless it’s good old Digger game, of course ;) ). It is unwise to use 56 bit DES keys to protect the personal data of bank customers.

Any protection should be adequate to the data it protects.