Let’s explore how this technology works and its main mechanisms and challenges.
Evolution of ZKP
The emergence and development of ZKP technology is associated with cryptography research conducted in the late 1980s. One of the first projects realized on the basis of ZKP was the Fiat-Shamir protocol proposed by Israeli professors of computer science and informatics Adi Shamir and Amos Fiat in 1986. Its functionality used a combination of hashing and pseudo-random numbers to generate a proof. This was what made it possible to ensure the confidentiality of information while proving its existence.
The process consisted of four basic steps, which became the core of ZKP in the future:
- Initiation. The recipient of the proof selects a random number and sends it to the proving party as a challenge.
- Proof generation. The prover receives the challenge and uses it to generate the proof. It applies a hash function to the combination of the challenge and the secret value, obtaining a pseudo-random number.
- Response. The prover sends the resulting pseudo-random number as a response to the recipient of the proof.
- Verification. The recipient verifies the proof by applying the same hash function to the combination of the challenge and the received response. If the result matches the original challenge, the proof is accepted.
The basic idea of the Fiat-Shamir protocol was that the hash function was publicly available and reversible, but it was practically impossible to go from the hash value to its original value. The Fiat-Shamir protocol was widely used in different authentication systems and e-money exchange protocols.
Later, ZKP technology became particularly popular in the context of the development of blockchain systems. ZKP was adapted for use within the development of various blockchain protocols to provide confidentiality and security of transactions, authentication, and other functions.
The first experiments with ZKP within Web3 projects and the realization of its potential were performed on the Ethereum blockchain, as it’s one of the most well-known and widely-used platforms for developing smart contracts and decentralized applications, and its flexibility enables the programming of complex logical conditions.
Some of the first successful ZKP protocols were zk-SNARK and zk-STARK. These protocols allow for complex computations based on encrypted data, providing a highly efficient and scalable ZKP. Both protocols have their own advantages and applications:
- zk-SNARK (Zero-Knowledge Succinct Non-Interactive Argument of Knowledge) is commonly used in applications that require compactness and lack interactivity. For example, ensuring the confidentiality of transactions in the blockchain network.
- zk-STARK (Zero-Knowledge Scalable Transparent Argument of Knowledge) is often used in cases that require scalability and transparency. For instance, for data privacy protection and complex computing.
Nowadays, ZKP technology keeps attracting the attention of researchers and developers, and the scope of its application and integration with other DLT solutions is actively growing, contributing to creating more efficient and private solutions.
ZKP Mechanisms
Let’s look at the basic mechanisms of ZKP technology to understand how it works. First, there are two parties involved in the process:
- the prover;
- the verifier.
The process involves four basic steps that have remained essentially unchanged since the Fiat-Shamir protocol was created. They are based on zero-knowledge proof mechanisms:
- Proof of Knowledge. This mechanism allows the prover to provide the proof that convinces the verifier that a particular statement is true instead of disclosing information.
- Proof of Execution. A mechanism that enables the prover to provide the proof that convinces the verifier that the action has been correctly executed.
- Proof of Consistency. An algorithm that allows the prover to provide the proof that shows that the information is identical and consistent on both sides without revealing the specific details of the data.
- Proof of Non-repudiation. This mechanism allows the prover to provide proof of data integrity, enabling the verifier to ensure that there has been no substitution or alteration.
ZKP uses different mathematical and cryptographic techniques in each of these mechanisms to create proofs that can be verified without directly disclosing the data. This ensures privacy and confidentiality in the transmission and processing of information while maintaining the trust and validity of proof.
Objectives and Goals of ZKP
Zero-knowledge proof (ZKP) technology, in addition to providing confidentiality and privacy of data, which is certainly its main goal, also addresses several other important objectives:
- Provides data security and integrity, enabling information validation without revealing its content, preventing the possibility of data modification in the process.
- Allows for authentication and proof of eligibility to access certain data or resources without revealing one’s identity or specific information.
- Expands the possibilities of blockchain, making it more attractive to various industries, as it can provide not only confidentiality of transactions but also data protection.
The versatility of ZKP technology makes it in demand beyond blockchain developers. Its mechanisms are used to provide secure access in various spheres that require ways of interaction and data processing with a higher level of privacy.
Barriers to Mass Adoption
Like any innovative technology, ZKP faces several obstacles that prevent its mass adoption. Among them are:
- Implementation complexity. Developing ZKP protocols requires substantial computational resources and specialized cryptographic techniques. The efficiency and performance of ZKP protocols must be considered so that they can scale and be applied in real-world environments.
- Vulnerability. Improper design and implementation of ZKP protocols can lead to security breaches.
- Scalability and performance. ZKP protocols often encounter problems when processing large amounts of data or when operating in distributed networks. In addition, the computational requirements of ZKP protocols are quite high, making it difficult to use them effectively.
- Regulation and regulatory issues. The use of ZKP, like other blockchain technologies, still lacks a clear regulatory framework, which limits the use of the technology on a large scale.
On the other hand, developers are actively experimenting with ZKP, so protocols based on this technology become more and more frequent examples of high-quality and efficient systems.
To summarize, ZKP has great prospects for the future outside of the blockchain industry, as the ability to maintain anonymity when working online is the most pressing issue in many areas. We should expect that in the near future, ZKP may globally change the principles of digital interaction with information.
