The algorithm Evaluate takes as input a public key pk, a circuit C, a tuple of ciphertexts
c = ([c.sub.1] [c.sub.2],...,[c.sub.t]),
On the other hand, in general HE often requires expensive computation and large memory storage due to its large ciphertexts
. Due to the resource limitations and constrained memories of wearable devices, it might be difficult to apply and implement HE in wearable devices.
of encryption, and explores when ciphertexts
, passwords, and plaintexts
From the table in , it is easy to realize that the two schemes in  do not support conjunctive keywords since they require nTGe + (n + 1)TGmul + nTGH in the generation of their ciphertexts
. We categorically state that our scheme is more efficient in the ciphertext
generation when n is sufficiently large.
Additionally, NuCypher's technology, called proxy re-encryption, is a type of public-key encryption that allows a third-party proxy to transform ciphertexts
from one public key to another (using re-encryption keys) without learning anything about the underlying message.
DFA retrieves the secret key based on information of the characteristics of the injected faults and the difference of the ciphertexts
and faulty ciphertexts
When an attribute revocation happens, the secret keys and ciphertexts
corresponding to that particular attribute need to be updated.
This can be formalized by giving a PPT algorithm D the possibility to choose two ciphertexts
[c.sub.1], [c.sub.2] and giving it oracle access to two instances of BlindDec based on these choices.
[mathematical expression not reproducible] is the number of ciphertexts
which is associated with the revoked attribute i.
In reader-device and ESP-device authentication, a public key based linearly homomorphic signature scheme is used to authenticate the device's identity and the ciphertexts
. It provides the strong defense for the Man-In-The-Middle attacks, since the attacker cannot convince the reader and ESP to accept its public key.