Many RESTful web services will want secure access to data and functionality they provide. This is especially true for services that will be performing updates. They will want to prevent sniffers on the network from reading their messages. They may also want to fine-tune which users are allowed to interact with a specific service and disallow certain actions for specific users. The Web and the umbrella specification for JAX-RS, Java EE, provide a core set of security services and protocols that you can leverage from within your RESTful web services. These include:
Authentication – Authentication is about validating the identity of a client that is trying to access your services. It usually involves checking to see if the client has provided an existing user with valid credentials, such as a password.
Authorization – Once a client is authenticated, it will want to interact with your RESTful web service. Authorization is about deciding whether or not a certain user is allowed to access and invoke on a specific URI. For example, you may want to allow write access (PUT/POST/DELETE operations) for one set of users and disallow it for others. Authorization is not part of any Internet protocol and is really the domain of your servlet container and Java EE.
Encryption – When a client is interacting with a RESTful web service, it is possible for hostile individuals to intercept network packets and read requests and responses if your HTTP connection is not secure. Sensitive data should be protected with cryptographic services like SSL. The Web defines the HTTPS protocol to leverage SSL and encryption.