7175fc9c-2cc8-4284-868d-8421df1d0dd320250716103337343wseas:wseasmdt@crossref.orgMDT DepositInternational Journal of Computational and Applied Mathematics & Computer Science2769-247710.37394/232028https://wseas.com/journals/camcs/index.php51920255192025510.37394/232028.2025.5https://wseas.com/journals/camcs/2025.phpMalikaYaiciComputer Department University of Bejaia Route de Targa Ouzemour, Bejaia, 06000 ALGERIAFerielLalaouiComputer Department University of Bejaia Route de Targa Ouzemour, Bejaia, 06000 ALGERIALydiaBelhoulComputer Department University of Bejaia Route de Targa Ouzemour, Bejaia, 06000 ALGERIAAs a new distributed point-to-point (P2P) technology, blockchain has become a very broad field of research, addressing various challenges including privacy preserving as is the case in all other technologies. In this work, a study of the existing solutions to the problems related to private life in general and in blockchains in particular is performed. 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