This trunk card delivers Dense Wavelength-Division Multiplexing (DWDM) transmission using a coherent polarization-multiplexed differential quadrature phase shift keying (CP-DQPSK) modulation scheme. The Cisco ONS 15454 100 Gbps Coherent DWDM trunk card simplifies the integration and transport of 100 Gigabit Ethernet and Optical Transport Unit Level 4 (OTU-4) interfaces and services into enterprises and service provider optical networks.