This paper presents Long Reach Wavelength Division Multiplexing Passive Optical Network (WDM-PON) system capable of delivering downstream 10 Gbit/s data and upstream 10 Gbit/s data on a single wavelength. The optical source for downstream data and upstream data is CW laser at central office and reflective semiconductor optical amplifier (RSOA) at each optical network unit. The use of dispersion management for both up and downstream transmission removes the error floor owing to the chromatic dispersion induced excess intensity noise. It has also been experimentally confirmed that both pre and post-dispersion compensating schemes are effective ways to suppress the intensity noise. Error free bidirectional transmission over 35 km is demonstrated by using Erbium-doped fiber amplifiers at the RN and at central office. Optical power budgets 14.565 dB and 29.171 dB are achieved for downstream performance and upstream performance respectively. This paper demonstrates an effective mitigation of Rayleigh backscattered noise for upstream data and downstream data and also demonstrates that receiver sensitivity is improved for upstream and downstream data. Bit error rate were measured to demonstrate the proposed scheme. In this paper long reach and large data service aspects of a WDM-PON is presented.Keywords: wavelength division multiplexing passive optical network (WDM-PON), reflective semiconductor optical amplifier (RSOA), Erbium doped fiber amplifier (EDFA), single mode fiber (SMF), photo detector (PD), arrayed waveguide grating (AWG), attenuator (ATT)