您必须对交易执行https，并使用SHA-1哈希和salt存储密码.

You must do https for the transaction and store password using SHA-1 hash and salt.

http://en.wikipedia.org/wiki/Salt_%28cryptography%29

添加一些示例:

http://www.obviex.com/samples/hash.aspx

http://www.aspheute.com/english/20040105.asp

http://csharptest.net/?p=470