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:
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