Cryptophon is an ISDN-Telephone with integrated voice encryption developed by Boris Floricic (also known as "Tron"). It was created during 1997 and 1998 for his diploma thesis ("Realisierung einer Verschlüsselungstechnik für Daten im ISDN-B-Kanal") at the Technische Fachhochschule Berlin. He planned to extend the phone so it would also be possible to encrypt data-connections.

• [ftp://ftp.ccc.de/documentation/cryptron/ Original Plans how to build the phone]
• http://vs.informatik.uni-kl.de/people/geraldy/Gera00.pdf