OC-768 is currently the fastest synchronous optical network (SONET) standard rate for data transmission on optical fiber as part of the broadband ISDN (BISDN). OC stands for optical carrier and the number affixed is the multiple of the base rate bandwidth of 51.85 Mbps. OC-768 supports rates of 40 gigabits per second (Gbps) on a fiber optic carrier, a rate that translates to the equivalent of seven CD-ROM's worth of data in one second. Developed to meet ever-growing demands for bandwidth, OC-768 uses dense wavelength division multiplexing (DWDM) to carry multiple channels of data on a single optic fiber. New DWDM systems are now in development to run at at 10 trillion bits per second (10 Tbps) per fiber. This translates into the theoretical capability of one fiber to support, simultaneously, an active Internet connection to every household in the U.S.
Enkido was the first company to offer OC-768 service, which they currently provide for a number of clients including Deutsche Telecom.