The Java EE 6 Tutorial, Volume I

When Should I Use JAX-WS?

JAX-WS addresses advanced quality of service (QoS) requirements commonly occurring in enterprise computing. When compared to JAX-RS, JAX-WS makes it easier to support the WS-* set of protocols (which provide standards for security and reliability, among other things) and interoperate with other WS-* conforming clients and servers.