Web Services Architecture and Its Specifications [Electronic resources] : Essentials for Understanding WS-* نسخه متنی

Dynamic Discovery

Dynamic Web service discovery is provided in a different manner. As an alternative to storing information in a known registry, dynamically discovered Web services explicitly announce their arrival and departure from the network. WS-Discovery defines protocols to announce and discover Web services through multicast messages.

When a Web service connects to a network, it announces its arrival by sending a Hello message. In the simplest case, these announcements are sent across the network using multicast protocolswe call this an ad hoc network. This approach also minimizes the need for polling on the network. To limit the amount of network traffic and optimize the discovery process, a system can include a Discovery Proxy. A Discovery Proxy replaces the need to send multicast Chapter 8, "Management."

Dynamic discovery also extends the Web services architecture to devices, such as those that might implement the Universal Plug & Play (UPnP) protocols today. This is an important step in making the architecture truly universal. With WS-Discovery and WS-Eventing, devices such as printers or storage media, for example, can be incorporated into a system as Web services without the need for specialized tools or protocols.