Study of tau reconstruction algorithms using pp collisions data collected at sqrt(s) = 7 TeV

Proton--proton collision events collected with the CMS experiment at LHC at a center--of--mass energy of $\sqrt{s} = 7$~TeV in 2010 are used to commission the algorithms for reconstruction and identification of tau lepton hadronic decays. Four different types of algorithms are considered: three based on particle--flow event reconstruction and one based on combinations of tracks and calorimeter clusters. Probabilities for quark and gluon jets to pass the tau identification criteria of the different algorithms are measured in data dominated by QCD multi--jet events and compared to predictions of Monte Carlo simulations.