The ADTRAN MX3112 Controller Card is a plug-in unit for the MX3 Chassis (P/N 1189001L1) that provides two application modes, Copper mode and DS3 mode. In Copper mode, the MX3112 provides twelve DS1 ports that can be bonded for transporting the traffic of up to four client Ethernet ports. In DS3 mode, sixteen of the DS3 tributaries can be bonded for transporting the traffic of up to four client Ethernet ports.