Common encryption of data

There are methods and devices (6, 7) provided to the common generating an encrypted text in a data processing system (5). The first unit (6) represents a first message (m The first message (M The first unit (6) generates an initial ciphertext (C1) in which the first message (m The initial consistency component (V1) is generated using the bilinear mapping panel. The first unit (6) sends the initial ciphertext (C1) to the second unit (7). The second unit (7), a second message (m After receiving the initial ciphertext (C1) generates the second unit (7) an updated encrypted text (C2), of an updated blinded encrypted message (E2) and an updated consistency component (V2) for evaluating the integrity of the updated encrypted text ( C2). The updated blinded encrypted message (E2) is produced by means of the public key using the initial blinded encrypted message (E1) and an encryption of the second message (m The updated consistency component (V2) is calculated using the initial consistency component (V1) and the bilinear mapping table generated. The second unit (7) sends the updated encrypted text (C2) to the first unit (6). After receiving the updated encrypted text (C2) unblinded the first unit (6) the updated blinded encrypted message (E2), to obtain a final encrypted message (E3), and generating a final ciphertext (C3), the final the encrypted message (E3) and a final consistency component (V3) for evaluating the integrity of the final encrypted text (C3). The final consistency component (V3) is measured using the updated consistency component (V2) and the bilinear mapping table generated.