Abstract: The paper studies the characteristics of the discrete optical fiber Raman amplifier on the base of PTDS, which is a simulation platform for optical transmission system emulation. Consequently, a discrete optical fiber Raman amplifier whose parameters have been optimized has been designed. Then a comparison of the improvement on the system capability has been carried through between EDFA and discrete FRA. From the comparison, the advantage of discrete FRA has appeared. At the end of the paper a project about achieving all Raman amplification in the optical fiber communication is presented.