A method for processing digital information, performed by a processing device, said digital information being stored in a plurality of segments (Si) in an external memory, comprising the steps of: loading a first integrity table (MAC-Table 1) containing a plurality of first integrity elements (Ai) respectively authenticating the plurality of segments of digital information (Si), and an associated digital signature of said plurality of first integrity elements (Ai), from the external memory to the processing device; verifying the digital signature associated with the first integrity table (MAC-Table 1), loading encrypted segments of digital information ([Si]) from the external memory to the processing device; loading separately integrity data ([Ai]|Bi) of the segments of digital information from the external memory, wherein the integrity data of each segment of digital information (Si) includes a first integrity element encrypted ([Ai]) and a second integrity element (Bi) authenticating encrypted data ([Si]|[Ai]) resulting from an encryption of said segment of digital information (Si) concatenated with said first integrity element (Si); and, for each segment of digital information (Si): concatenating the encrypted segment of digital information ([Si]) that has been loaded to the processing device and the corresponding integrity data loaded separately ([Ai]|Bi); verifying the integrity of the encrypted segment of digital information ([Si]) concatenated with the first integrity element encrypted ([Ai]) using the second integrity element (Bi); decrypting the segment of digital information (Si) and the first integrity element (Ai) and outputting the segment of digital information and the first integrity element concatenated together (Si|Ai); verifying the integrity of the segment of digital information using the concatenated first integrity element (Ai); checking that the first integrity element (Ai) matches a corresponding first integrity element in the first integrity table (MAC-Table 1); processing the segment of digital information (Si). loading a first integrity table (MAC-Table 1) containing a plurality of first integrity elements (Ai) respectively authenticating the plurality of segments of digital information (Si), and an associated digital signature of said plurality of first integrity elements (Ai), from the external memory to the processing device; verifying the digital signature associated with the first integrity table (MAC-Table 1), loading encrypted segments of digital information ([Si]) from the external memory to the processing device; loading separately integrity data ([Ai]|Bi) of the segments of digital information from the external memory, wherein the integrity data of each segment of digital information (Si) includes a first integrity element encrypted ([Ai]) and a second integrity element (Bi) authenticating encrypted data ([Si]|[Ai]) resulting from an encryption of said segment of digital information (Si) concatenated with said first integrity element (Si); and, for each segment of digital information (Si): concatenating the encrypted segment of digital information ([Si]) that has been loaded to the processing device and the corresponding integrity data loaded separately ([Ai]|Bi); verifying the integrity of the encrypted segment of digital information ([Si]) concatenated with the first integrity element encrypted ([Ai]) using the second integrity element (Bi); decrypting the segment of digital information (Si) and the first integrity element (Ai) and outputting the segment of digital information and the first integrity element concatenated together (Si|Ai); verifying the integrity of the segment of digital information using the concatenated first integrity element (Ai); checking that the first integrity element (Ai) matches a corresponding first integrity element in the first integrity table (MAC-Table 1); processing the segment of digital information (Si). concatenating the encrypted segment of digital information ([Si]) that has been loaded to the processing device and the corresponding integrity data loaded separately ([Ai]|Bi); verifying the integrity of the encrypted segment of digital information ([Si]) concatenated with the first integrity element encrypted ([Ai]) using the second integrity element (Bi); decrypting the segment of digital information (Si) and the first integrity element (Ai) and outputting the segment of digital information and the first integrity element concatenated together (Si|Ai); verifying the integrity of the segment of digital information using the concatenated first integrity element (Ai); checking that the first integrity element (Ai) matches a corresponding first integrity element in the first integrity table (MAC-Table 1); processing the segment of digital information (Si).