The spectral width of the continuous wave broadband generated in an erbium doped fiber ring laser containing a dispersion shifted fiber (DSF) in a filterless cavity is found to be governed by the nature of the gain spectrum of the doped fiber, in addition to the nonlinear effects. This dependence is studied experimentally with different lengths of the doped fiber and the DSF. Spectral broadening is demonstrated in the conventional (C) and long wavelength (L) bands using pump powers less than 200 mW, with an appropriate choice of cavity parameters. The generated broadband is demultiplexed in the C -band to prove its utility in optical communication systems. © 2008 American Institute of Physics.