Password encryption

…In this chapter, we will discuss encryption and user authentication.…Authentication has become ubiquitous on the web.…Most web applications have password protected areas.…Sometimes even the whole site requires you to log in.…It's important to go over this topic because it's very easy to get it wrong.…And getting it wrong, can be very costly.…Lets begin by talking about password encryption.…The number one rule of user authentication is never store passwords in plain text.…I can't stress this point strongly enough.…This is the minimum amount of security that you…must offer if you're going to have user authentication.…

If you store passwords in plain text, you compromise users on your…site but you also compromise users on other sites all across the internet.…For the simply reason that users often reuse their passwords in multiple places.…So please, for my sake, don't do it.…It's also bad idea to store passwords that can be decrypted.…While an encrypted password might seem to…be automatically secure that's not necessarily the case.…