Table 2 Computational limitation of traditional model comparison.

From: Secure facial biometric authentication in smart cities using multimodal methodology

Sl. No

Model

Encryption

Disadvantages

Proposed advantages

1

Standalone CNN

RSA

Due to the vanishing gradient problem, more computational effort is required to provide privacy using the RSA encryption technique.

The fused model performs well in handling gradient problems and requires low computational effort to process privacy using ElGamal encryption.

2

ResNet-50

RSA

Processing the output takes longer time because it utilizes RSA with modular exponentiation, which requires larger key sizes.

The fused model utilizes CNN to reduce computational complexity and speed up the process, while ElGamal encryption offers a higher level of security than RSA.

3

VGG-16

RSA

Compared to CNN and ResNet-50, a larger number of parameters are used which increases the computational complexity.

ResNet-50 uses minimum parameters when fused with CNN and has achieved better performance and enhanced privacy preservation using ElGamal encryption.