balance by transferring zero-knowledge proofs, exclusive of enlightening the account balance. “Succinct Non-interactive Argument of Knowledge” is one of the extensions of zero-knowledge designed to support the Zcash procedure.
1.8.7 The Trusted Execution Environment (TEE)
TEE offers an entirely remote atmosphere for appliance executions, efficiently checking additional software appliances plus operating systems from being corrupt or tamper. The Intel Software Guard Extension (SGX) is a delegate skill to apply a TEE in various domains, especially in blockchain appliances. Multiple aspects are subjective for credit scoring: the quantity and nature of financial records, payment reports, and credit exploitation.
1.8.8 Game-Based Smart Contracts (GBSC)
GBSC designed based on a verification game that decides whether a computational assignment is properly executed or not. Moreover, in every stage of the “verification game”, the verifier persistently tests less critical subsection of the calculation that permits TrueBit to diminish the commutating load on its nodes significantly.
1.9 Challenges of Blockchain
Blockchain is an incredible invention of this decade; at the same time, it has some significant challenges, which we discussed below. Even though considerable challenges, they can easily triumph over the ripeness and enrichment of the blockchain skill in the coming future.
1.9.1 Scalability
Due to the high volume of blockchain and its characteristics enhancement, the number of digital transactions also increased exponentially. Every transaction must store in a node block for authorization. The foundation of existing transactions desires to be legalized primary than the transaction deal to be authenticated. The adequate block size and then the intermission times play a huge role in introducing new blocks into the system. In some situations, the blocks’ size may build unauthorized transaction delays in minute transactions since miners or clients mostly prefer to execute and prefer transactions for high transactional fees. By taking all these operations, scalability is a big issue in blockchain, and it classifies into storage optimization. Lightweight client or miner utilized to fix the scalability concern and redesigning of blockchains— where blockchain scattered into a critical block responsible for the leadership elections, a micro block accountable for business deal storing.
1.9.2 Privacy Outflow
When everyone on the network accesses the public keys, the blockchain defenseless against denial-of-service attacks leads to the outflow of transactional data. To overcome all these, various authors proposed dissimilar actions, those classified into mixing solution: Mixing suggests anonymity through transferring finances from manifold input address to manifold output addresses. Anonymous is another effective solution that unlinks the payment genesis for a transaction.
1.9.3 Selfish Mining
In selfish mining, some nasty or wicked miners or clients store the mined blocks in their database and tries to create a confidential branch that transmits only after reaching specific requirements. In such scenarios, truthful or sincere miners waste lots of time and resources since selfish miners or clients organize private chains.
1.9.4 Security
Security describes confidentiality, truthfulness, and availability, which are challenging tasks in public blockchains where keys are visible to all nodes. Confidentiality level is low in scattered systems, and truthfulness is the profession of blockchains; even though it faces different issues, accessibility in blockchains is high in terms of legibility compared to writing accessibility.
1.10 Conclusion
Blockchain is a broadly renowned technology, which got massive interest from various research communities around the world. It consists of different key techniques that support various requirements in different human life areas like healthcare, financial transactions, elections, and markets. However, it faces many challenges associated with security and privacy. So, in this chapter, we made a systematic study on blockchain safety measurements in recent years. We made an explicit discussion on blockchain development, working procedure, structure and key technologies, and IoT inclusion with blockchain. Moreover, we described various security and privacy properties and respective practices; finally, we discussed challenges in the blockchain.
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