Abstract : A model of TDFA has been proposed based on simulation after considering all the major parameters like pump and signal power, without considering ASE. Through this analysis of TDFA the optimum value of pump power and the range of fiber length (TDF) have been evaluated. In this section, an effort has further been made to use the least possible fiber length of TDF so as to maximum possible gain and in turn cheaper amplifier. The present research claims to support 96 DWDM channels across 1479nm-1555nm wavelength range with a channel spacing of 0.8nm. The optimum range of fiber length of TDFA has been evaluated between 8m-16m. The peak gain of ranging from 22 dB to 30.5dB has been attained for selected optimum fiber lengths ranging from 8m to 16m of TDF. Keywords: ASE,DWDM, TDF, TDFA, Fiber length, Gain