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NEMA ANSI C12.21:2006

Protocol specification for telephone modem communication

Details the criteria required for communications between a C12.21 device and a C12.21 client via a modem connected to the switched telephone network. The C12.21 client could be a laptop or portable computer, a master station system or some other electronic communications device.

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NEMA: National Electrical Manufacturers Association [NEMA]


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