We report the experimental demonstration of all-optical
wavelength multicasting of OC-768 (40 Gbps) channel using
a single-pass, pump modulated parametric amplifier. The performances
of 1-to-20 and 1-to-40 multicasting with excellent signal fidelity
were observed. The impairment mechanisms were identified
from cascaded filtering, linear and nonlinear crosstalk. It is shown
that the parametric amplifier offers a wide range of operation characterized
by minimal multicast penalty.We show that all multicast
channels have an error free performance with Q factors well above
the forward error correction (FEC) limit within the designed operating
range.