E1.31 (also called Streaming ACN) is a protocol for sending DMX512 data over the ACN (E1.17) family of protocols. Developed by ESTA, the specification is available at http://www.esta.org/tsp/documents/published_docs.php. E1.31 is expected to become the new standard for transporting DMX over IP, replacing other protocols such as ArtNet and Shownet. For a list of devices / software that supports E1.31 see E1.31 Devices.
E1.31 works by adding a framing layer between the Root Layer and the DMP Layer. This new layer (called the E1.31 layer) adds properties such as the universe number, the source priority & sequence numbers.
The standardized version of E1.31 is 0.46. A pre-release specification was published as version 0.2 which is implemented by some software.
From http://www.esta.org/tsp/working_groups/CP/projs.html, E1.33 is expected to extend E1.31 to support RDM.
Entertainment Technology -- USITT DMX512-A -- Asynchronous Serial Digital Data Transmission Standard for Controlling Lighting Equipment and Accessories . See DMX
The above is found via http://webstore.ansi.org/
Note that DMX512-A was updated in 2004 and again in 2008: http://www.esta.org/tsp/news/newsdetails.php?newsID=291 (regarding text mesasges in UTF-8, update rate almost up to 20*44 Hz, corrections of errors and clarifications)
The RDM protocol is to be extended with BSR E1.37 e.g. for bulk data transfer.