With the advent in the near future of radio telescopes as SKA and LOFAR,
a new window on the high-redshift universe will be opened. In particular,
it will be possible, for the first time, to map the temporal evolution
of cosmic reionization through the 21cm signal from the diffuse
intergalactic medium (IGM).
In this talk I will present the latest results on simulations of IGM
reionization, based on a combination of high resolution N-body simulations
(to describe the dark matter and diffuse gas component), a semi-analitic
model of galaxy formation (to track the evolution of the sources of
ionizing radiation) and the radiative transfer code CRASH (to accurately
follow the propagation of ionizing photons into the IGM).
Finally, I will discuss the observability of the 21cm signal from the
diffuse IGM, expected in the simulated reionization history.