Message confidentiality typically means that a sender encrypts the message to be transmitted using the session key through symmetric cryptography; then, the session key is encrypted employing a receiver's public key; finally, the resulting ciphertext
is sent with the encrypted symmetric key (ESK) to the receiver.
Furthermore, as all of the existing schemes based on the blueprint of Gentry's scheme, each ciphertext
generated has noise attached for security reason.
Whenever a homomorphic operation is applied, some noise will be added into the ciphertext
and then the ciphertext-size increases.
infeasible to determine whether a ciphertext
is an encryption of
The result of XOR is called ciphertext
or encrypted text.
With this, the same data becomes the same ciphertext
after encryption, and it enables the cloud server to deduplicate while ensuring confidentiality.
Cloud encryption is the change of a cloud benefit client's information into ciphertext
. Cloud encryption is practically indistinguishable to in-house encryption with one vital contrast that the cloud client must set aside opportunity to find out about the supplier's strategies and methodology for encryption and encryption key administration.
Most of the existing CP-ABE scheme uses bilinear maps and generates secret keys and ciphertext
of large size.
The cipher will then be XOR-ed with plaintext to produce the ciphertext
. For the A5/1 stream cipher, the secret key produced will eventually XOR-ed with 228-bit frames of GSM conversation which are transmitted every 4.6 milliseconds [27,28].
The algorithm will encrypt M and create a ciphertext
CT such that only a user that possesses a set of attributes that satisfies the access structure will be able to decrypt the message.
To be compatible with the data aggregation, we also propose a linearly homomorphic signature scheme which is used to sign the ciphertext
of metering data.