The WSD Port Monitor is a new printer port monitor in Windows Vista and Windows Server 2008. This port monitor supports printing to network devices that are designed to include Web Services for Devices (WSD) technology. Web Services for Devices allows network-connected IP-based devices to advertise their functionality and offer these services to clients by using the Web Services protocol. WSD-based devices and clients communicate over the network using a series of SOAP (Simple Object Access Protocol) messages over UDP and HTTP(S). WSD for Devices provides a network plug-and-play experience that is similar to installing a USB device. Web Services for Devices also defines a security profile that may be extended to provide additional protection and authentication using device-based certificates.