  Up-to-date estimates of the cosmological parameters are presented as a result
of numerical simulations of cosmic microwave background and large scale
structure, considering a flat Universe in which the dark matter is made
entirely or partly of mirror matter, and the primordial perturbations are
scalar adiabatic and in linear regime. A statistical analysis using the Markov
Chain Monte Carlo method allows to obtain constraints of the cosmological
parameters. As a result, we show that a Universe with pure mirror dark matter
is statistically equivalent to the case of an admixture with cold dark matter.
The upper limits for the ratio of the temperatures of ordinary and mirror
sectors are around 0.3 for both the cosmological models, that show the presence
of a dominant fraction of mirror matter, $0.06 \lesssim \Omega_{\rm mirror} h^2
\lesssim 0.12$.
