Article 5(1) of Directive 2002/58 provides that Member States must ensure the confidentiality of communications by means of a public communications network and publicly available electronic communications services, and of the related traffic data, and must inter alia prohibit, in principle, the storage of that data by persons other than users, without the consent of the users concerned. The only exceptions relate to persons lawfully authorised in accordance with Article 15(1) of that directive and the technical storage necessary for conveyance of a communication. In addition, as regards traffic data, Article 6(1) of Directive 2002/58 provides that stored traffic data must be erased or made anonymous when it is no longer needed for the purpose of the transmission of a communication without prejudice to paragraphs 2, 3 and 5 of that article and Article 15(1) of the directive.