Many vendors use the Universal Plug and Play (UPnP) architecture to configure routers, firewalls, and other Internet Gateway Devices (IGDs). UPnP is essentially a set of protocols that define how a device should interact with a PC and how a PC should interact with a device.

UPnP devices advertise services that perform specific functions. For example, an IGD would expose a service that connects across a WAN such as the Internet and another service that enables a user to configure the device. These services announce themselves and are discovered by other devices on a network by using the Simple Service Discovery Protocol (SSDP). After an application has discovered a particular device and its services on a network, it can query and modify the service's properties or call the device service's functions.

Windows XP has native support for UPnP. If you install this support, you can control your UPnP-enabled network routers from the XP Network Connection folder's Internet Connection applet. Likewise, network-based media players (also known as media renderers), such as Roku Labs' SoundBridge, use UPnP to fetch lists of music to play from a PC running hosting software such as Windows Media Connect.

You can find more information about UPnP at the official UPnP Web site, And you can find information about the different properties that you can query and modify in an IGD at