Vulnerability to chosen-cyphertext attacks of optical encryption schemes based on double random phase keys

Universitat de Barcelona, Departament de FĂ­sica Aplicada i Optica, Diagonal 647, 08028 Barcelona, Spain.
Optics Letters (Impact Factor: 3.18). 08/2005; 30(13):1644-6. DOI: 10.1364/OL.30.001644
Source: PubMed

ABSTRACT We show how optical encryption methods based on double random phase keys are vulnerable to an organized attack of the chosen-ciphertext type. The decryption key can be easily obtained by an opponent who has repeated access to either the encryption or decryption machines. However, we have also devised a solution that prevents the attack. Our results cast doubts on the present security of these techniques.

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