In the proposed method the private cloud is provided with a trapdoor key to transfer the cipher text
over one access policy to other access policies.
A token is generated for the credit card number, and stored alongside the cipher text
in the token vault (Token database).
After the KSA, the PRGA performs additional swapping operations between state[i] and state[i+1], and between state[j] and state[j+1], to generate the key stream that will XORed with the plaintext to get the cipher text
The encryption time can be measured as the time that an encryption algorithm takes to produce a cipher text
from a plaintext.
The existing stream ciphers are vulnerable to frequency analysis attack, brute force attack, correlation attack, algebraic attack known plain text attack, cipher text
only attack, etc.
The simulation results show that the scrambling degree of the encrypted image is high and the correlation between adjacent pixels is small, the anti-aggressively is stronger and the security is higher, through the analysis of the correlation between plaintext and cipher text
image, we made a further proof that the encryption image has better effect.
 designed a privacy-preserving face recognition protocol based on additive homomorphic encryption, in which Euclidean distances between feature vectors or finding a minimum are computed by using the homomorphic property of the cipher texts
. The protocol of Erkin requires large network traffic and a large memory, which makes those systems less practical.
One-time pad encryption removes bit dependencies in cipher texts
if the key used has its bits independent.
This hidden information can be plain text, cipher text
(unintelligible) or images.
: This is the scrambled message produced as output.
Trying to fit the larger cipher text
of a I6-digit credit card number back into the 16-digit field poses a "square peg into a round hole" kind of storage problem with consequences that ripple through the business applications that use the data.