J2EE™ Security for Servlets, EJBs and Web Services: Applying Theory and Standards to Practice

Practical Applications

Now that we have looked at most of the basic cryptographic services and have an idea of how they work, let us ask this question: What good are they? What can they do for us? As we have been saying all along, despite the abstract nature, cryptography is quite useful and can do pretty mighty things.

Confidentiality. Encrypted information is virtually hidden from everyone who doesn't know how to decrypt it or doesn't have the appropriate key. This makes it possible to share secret information over insecure communication channels, such as the Internet, thus providing confidentiality even though the network itself is quite open. The same applies to data stored on disk. Encryption ensures confidentiality of stored data even if ...