FRITZ! ISDN-Controller C4, ISDN, 14.4 Kbit/s, Wired, Full-duplex, ITU V.21, ITU V.22, ITU V.22bis, ITU V.29, ITU V.32, ITU V.32bis, ITU V.34, ITU V.17, ITU V.27ter,..., 16 MB FRITZ! ISDN-Controller C4. Data link protocols: ISDN. Modem speed: 14.4 Kbit/s, Connectivity technology: Wired, Transmission method: Full-duplex. Minimum RAM: 16 MB, Minimum processor: StrongARM SA-110 233 MHz