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lessly. You should, for example, be able to plug your laptop computer into a hotel network jack somewhere and be able to use
the printer, without going through a lot of network configuration gobbledygook. The network vision extends beyond these
traditional devices, however, to things like mobile telephones, pagers, Personal Digital Assistants, and, of course, LEGO
robots. A detailed article on this demonstration (including source code) is here:
http://developer.javasoft.com/developer/technicalArticles/ConsumerProducts/JavaTanks/Javatanks.html
At one of the keynote speeches for the 1999 JavaOne conference, in fact, a demonstration of JINI included LEGO robots as
JINI devices. Unfortunately, JINI doesn't actually run on the RCX. A proxy system is used instead, such that a JINI proxy runs
on a PC, which, in turn, communicates with the robot over the IR link. However, it still makes for an interesting technology
blend.Independent of the JavaOne demonstration, Jan Newmarch has written a JINI tutorial that includes examples with LEGO
robots. You can read it for yourself here:
http://pandonia.canberra.edu.au/java/jini/tutorial/jini.xml
LEGO Network Protocol
LEGO Network Protocol (LNP) would allow two or more RCXs to communicate via their IR ports without prior configuration.
While it is possible to exchange messages between multiple RCXs by reserving blocks of message numbers for specific RCX-
to-RCX conduits, it's not a generalized solution. LNP is a more general approach, but it's still a work in progress. For more
information, see the discussion lists at LUGNET. Here's a discussion from mid-1999:
http://www.lugnet.com/robotics/rcx/legos/?n=180&t=i&v=c