  I report on a critical analysis of the scenario of electroweak baryogenesis
mediated by nonsuperconducting cosmic strings. This mechanism relies upon
electroweak symmetry restoration in a region around cosmic strings, where
sphalerons would be unsuppressed. I discuss the various problems this scenario
has to face, presenting a careful computation of the sphaleron rates inside the
strings, of the chemical potential for chiral number and of the efficiency of
baryogenesis in different regimes of string networks. The conclusion is that
the asymmetry in baryon number generated by this scenario is smaller than the
observed value by at least 10 orders of magnitude.
