Abstract
The strength of the crypto-semantic method (CSM) of text data protection based on the use of lexicographical systems in the form of applied linguistic corpora within the formally defined restrictions of selected spheres of applied uses has been analyzed. The levels of cryptographic strength provided by the crypto-semantic method of data protection with due regard of a cryptanalyst's resource capabilities are determined. The conditions under which the CSM provides absolute guarantee of text data protection from confidentiality compromise are determined.