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GSM handset like the Motorola C123 and talk to GSM-R BTSs. Of course you still need to implement the GSM-R specific features on layer 3 like ASCI. In both cases I think the hardware is there for whoever has a serious interest in experimenting with this technology, and who is not afraid to implement the GSM-R specific bits. -- - Harald Welte <laforge@gnumonks.org> http://laforge.gnumonks.org/ ============================================================================ "Privacy in residential applications is a desirable marketing option." (ETSI EN 300 175-7 Ch. A6)