A system, comprising: a wavelength division multiplexing, WDM, transceiver module having: an optical port including: a data transmit optical fiber connector and a data receive optical fiber connector; and a laser source-in optical fiber connector configured to a. couple to a laser source external to the WDM transceiver module, and b. provide polarization alignment for a polarization-maintaining fiber, and an optical modulator operatively coupled to the optical port, the optical modulator configured to receive a laser output from an external laser source via the polarization-maintaining fiber and modulate the laser output based on analog electrical signals generated by a digital signal processor; and a control unit configured to receive a second laser output data from the external laser source and a first laser output data from the WDM transceiver module, the control unit configured to: analyze the first laser output data and the second laser output data so as to determine information related to laser transmission conditions of the WDM transceiver module; and generate a control message for transmission to the external laser source based on the determined information, the WDM transceiver module a. not including an onboard laser source and b. being operatively coupleable to or capable of being integrated into a host board. a wavelength division multiplexing, WDM, transceiver module having: an optical port including: a data transmit optical fiber connector and a data receive optical fiber connector; and a laser source-in optical fiber connector configured to a. couple to a laser source external to the WDM transceiver module, and b. provide polarization alignment for a polarization-maintaining fiber, and an optical modulator operatively coupled to the optical port, the optical modulator configured to receive a laser output from an external laser source via the polarization-maintaining fiber and modulate the laser output based on analog electrical signals generated by a digital signal processor; and an optical port including: a data transmit optical fiber connector and a data receive optical fiber connector; and a laser source-in optical fiber connector configured to a. couple to a laser source external to the WDM transceiver module, and b. provide polarization alignment for a polarization-maintaining fiber, and a data transmit optical fiber connector and a data receive optical fiber connector; and a laser source-in optical fiber connector configured to a. couple to a laser source external to the WDM transceiver module, and b. provide polarization alignment for a polarization-maintaining fiber, and source external to the WDM transceiver module, and b. provide polarization alignment for a polarization-maintaining fiber, and an optical modulator operatively coupled to the optical port, the optical modulator configured to receive a laser output from an external laser source via the polarization-maintaining fiber and modulate the laser output based on analog electrical signals generated by a digital signal processor; and a control unit configured to receive a second laser output data from the external laser source and a first laser output data from the WDM transceiver module, the control unit configured to: analyze the first laser output data and the second laser output data so as to determine information related to laser transmission conditions of the WDM transceiver module; and generate a control message for transmission to the external laser source based on the determined information, the WDM transceiver module a. not including an onboard laser source and b. being operatively coupleable to or capable of being integrated into a host board. analyze the first laser output data and the second laser output data so as to determine information related to laser transmission conditions of the WDM transceiver module; and generate a control message for transmission to the external laser source based on the determined information, the WDM transceiver module a. not including an onboard laser source and b. being operatively coupleable to or capable of being integrated into a host board.