UPnP service for autonomous devices

Plug and Play (PnP) characterizes the ease with which new equipment can be installed in a computer system. Technically, the operating system recognizes the peripheral that has just been added to the computer, finds the driver needed to make it work, or asks to load this driver, and starts work after readjusting its parameters to take the new device into account. Hardware installation is thus greatly simplified by the automatic configuration of driver parameters, such as the interrupt used, the range of I/O ports employed, and so on.

"Universal Plug and Play (UPnP) takes the concepts of PnP and extends them to the whole network, facilitating the discovery and control of devices such as a network printer, ADSL router or any other peripheral equipment now connected to the local network. This technology is not the only one to offer such an approach.

In the first part of this document, we will compare the main features of UPnP with more or less similar technologies, such as Bonjour, SLP and Bluetooth, particularly in terms of the search and discovery protocols used. We'll see that one of UPnP's strong and specific features is the use of protocols very similar to those already tried and tested in the Web Services field.

In the second part, we present the general UPnP architecture, broken down into UPnP devices (servers) and control points (clients) on the network, as well as the associated standardized interfaces.

In the third section, we'll take a closer look at the UPnP protocol stack, before dwelling on the software implementation of UPnP in the fourth section. In conclusion, we'll highlight the prospects opened up by this new technology, which, over and above its primary vocation and its proximity to Web services, clearly lays the foundations for an extension to Web services for devices.