Table 5 Computational complexity of original DGK [17, 25], the IDCP, and the EPPCP
From: An efficient privacy-preserving comparison protocol in smart metering systems
Function | Original DGK | IDCP | EPPCP |
|---|---|---|---|
Encryption | 1Paillier+ℓ DGK | 1Paillier+ℓ DGK | 1Paillier+ℓ DGK |
Decryption | 1Paillier | 1Paillier | \(\left (\frac {1}{\rho }\right)_{\text {Paillier}}\) |
DGK zero-check | ℓ | ℓ | ℓ |
Multiplication | ℓ(ℓ+2) | \(\sim \frac {\ell (\ell +11)}{4}\) | ℓ |
Exponentiation (+) | ℓ | ℓ | 0 |
Exponentiation (−) | \(\frac {\ell (\ell +1)}{2}\) | \(\sim \frac {\ell (\ell +3)}{4}\) | 0 |