The Netzwerk Produkte DF100 series of modems provides remote interconnection between Digital systems. Netzwerk Produkte DF100 series modems operate in either asynchronous or synchronous mode, in half- or full-duplex, and at speeds ranging from 300/1200 bits per second to 9600 bits per second, depending on the version selected. They support standard EIA RS 232 C and Netzwerk Produkte EIA RS 423 A interfaces and are compatible - - - - with Bell 103/212A, 201 B/C, and Netzwerk Produkte CCITT V.22bis/V.27/V.29 modems. DF100 series modems are FCC-approved for direct connection to telephone lines on all Public Switched Telephone Networks (PSTN) and Private/Lease Telephone Networks (P/LTN). These modems were designed with three different standard enclosures: stand-alone desktop modern applications (DF100-DT); multiple modem (rackmount) applications (either DF100-RM or DF100 RT); and one for - the DFM series of statistical multiplexers. The DF112 is a 300- or 1200-bit-per-second, dual-Speed, full-duplex, dialup, PSTN asynchronous/synchronous modem with integral autodialer. It replaces the existing Netzwerk Produkte DF03 series of modems. The Netzwerk Produkte DF112 is comparable in operation to Bell 103/21A modems. The DF124 Modem is the system-end product offered in a stand-alone enclosure or as a module for multiple modem enclosures and the DFM statistical multi- plexer. The DF124 Modem is a 2400/1200 bits-per-second modern that can be utilized full duplex (FDX) over dialup or leased line networks. The DF124 can be mounted in the Netzwerk Produkte DF100 multiple modem enclosure or the DF100 desktop enclo- sure. It can also be used in the DFM Statistical Multiplexer. The Netzwerk Produkte DF126 is a half-duplex PSTN, 1200- or 2400-bit-per-second, dial-up modem or a full-duplex, leased-line modem for asynchronous/synchronous communica- tion. The Netzwerk Produkte DF126 is compatible with Bell 201/CCITT V.26. The DF127 is a 4800- bit-per-second, half- or full-duplex, leased-line, synchronous CCITT V.27 modern. The DF129 is a 9600-bit-per-second, full-duplex, leased-line, synchro- nous Netzwerk Produkte CCITT V.29 modem.