The performance of a cost-effective optical comb source using commercial off the shelf (COTS) components in a WDM passive optical network is demonstrated. Eight comb modes are individually modulated at 10.7Gb/s and transmitted over 50km of single mode fiber for downlink transmission, Error free performance is obtained for each comb line and a maximum performance difference of 1.4dB is experienced between the eight channels. Colorless operation of the optical network unit is achieved by utilizing an integrated module consisting of a tunable laser and an electro-absorption modulator as an uplink transmitter. Finally the predicted downstream performance of the system, when all the channels are transmitted simultaneously, is numerically simulated. © 2010 Optical Society of America.