# A Novel Digital Signature Scheme for Advanced Asymmetric Encryption Techniques
## 2 Related Work
However, this algorithm is unsuitable for constrained devices that are limited in resource computation. To improve the ECDCA's computational cost, [PERSON] in [29] proposed two schemes named ECDSA 1 and ECDSA 2. [PERSON]'s goal is to improve the ECDCA's computational cost while keeping the same security level as compared to the ECDSA. ECDSA 1 is suitable for constrained devices on the signatory's side, whereas ECDSA 2 is relevant for constrained devices on the verifier's side. In [30], [PERSON] and [PERSON] designed a Lightweight Digital Signature Algorithm (LWDSA) based on the ECDSA and cryptographic hash functions dedicated to WSNs. In this modified the ECDSA, the major variation is using the MBLAKE2b hash function instead of SHA-1 to generate the hash code. The LWDSA outputs have been compared with the traditional authentication process of the ECDSA. The analysis of the QoS parameters such as the latency, energy, throughput, etc., were performed over a 30-node network simulated in NS-2. Their simulation performed better by reducing the computation time and energy consumption, increasing the network lifetime. However, the computation time has not been clearly indicated for the generation and verification of the signature process. In addition, it is challenging to measure QoS parameters for a large-scale and dynamic WSN network in order to validate the proposed scheme. [PERSON] et al. aimed to develop an Enhanced Digital Signature Algorithm (EDSA) in [31] to ensure the integrity and secure access of the data stored in the cloud. The idea of EDSA focuses on elliptic curve square points generated by improved equations. The proposed EDSA generates two elliptic curves by applying the improved equations, which are used as public keys to perform the signing and verification process. In addition, a new basic formula is introduced for performing digital signature operations such as signing, verifying, and comparing. A compression technique is used to reinforce reducing the bit size of the signature. A new digital signature scheme based on Iterated Function Systems (IFSs) was designed in [32] by [PERSON] et al. Fractals were used to design the digital signature system based on IFS transformations. The receiver requests a signature from the signer, who then delivers a fractal signature to the requester without knowing the content of the message. The proposed scheme includes initialization, signing, extraction, and verification. The advantage of the fractal is that only a few parameters must be stored. The fractal scheme outperforms the DSA and RSA schemes due to the lower computational overhead and smaller key sizes. However, the scheme still incurs high computational overhead for constrained devices and needs to be adapted to such device types. In [33], [PERSON] et al. proposed a new attribute-based proxy signature scheme on a lattice that can resist quantum attacks. The scheme has the properties of both attribute-based signatures and proxy signatures providing fine-grained access control. The scheme allows the original signer to sign a warrant using their attribute keys to delegate signing authority. Then, the proxy signer signs the message only when the attribute set of the original signer satisfies the access structure and the warrant is valid. The verifier also checks the original signer's attributes and the validity of the signature. This feature provides fine-grained access control; however, the main disadvantage of lattice-based constructions is that they generally involve operations on, and storage of, large \(n\times n\) matrices. This resulted in the schemes being rather inefficient and unsuitable for practical use. [PERSON] et al. proposed a mixed private and consortium-based blockchain in [34] to realize the secure storage of medical cyber physical data. In the system, a threshold signature system based on blockchain was proposed for joint consultation.