10G OTU(OEO) Business Card is a 4-channel 10G service access card, its main function is to finish the 3R regeneration of any 4-channel signals under any protocol within the rate of 1.25 Gbit/s~11.3 Gbit/s to be accessed, and then convert them to optical signals of a standard DWDM wavelength or standard CWDM wavelength, so that the multiplexing unit can conduct WDM for optical signals of different wavelengths and also achieve the inverse process of the above process. It’s applicable to the wavelength division transmission solution for any access of services with the rate of 10G or below.