ACN - Architecture for Control Networks
ACN is a suite of documents that specifies an architecture, including protocols and language, which may be configured and combined with other standard protocols to form flexible, networked audio, lighting, or other control systems. It can be implemented on networks that support UDP, IP, and related protocols. It is not bound to Ethernet as a transport medium, but Ethernet is an obvious choice.
The ACN specification is being distributed via download as a 5MB archive of 17 PDF and two DDL files. The "hardcopy" is a CDROM; there is no paper version offered.
Wikipedia article on ACN: http://en.wikipedia.org/wiki/Architecture_for_Control_Networks
Article on ACN in PLSN magazine: http://www.plsn.com/index.php?option=com_content&task=view&id=1437&Itemid=101
The Open ACN Project Wants to make an open source implementation.
This is their wiki:http://openacn.wiki.sourceforge.net/ .