SonosWeb

A perl script runs and emulates a HTTP server and acts as an UPnP Control Point. The HTTP server portion handles all the requests from the UI, while the UPnP Control Point portion talks to the Sonos boxes.

This design was used so Apache or another web server isn't required. UPnP requires that a piece of software is always running to listen for UPnP Events, which is why traditional CGI software can't be used.