appXchain: Application-Level Interoperability for Blockchain Networks

Abstract

Blockchain technology has the potential to revolutionize industries by offering decentralized, transparent, data provenance, auditable, reliable, and trustworthy features. However, cross-chain interoperability is one of the crucial challenges preventing widespread adoption of blockchain applications. Cross-chain interoperability represents the ability for one blockchain network to interact and share data with another blockchain network. Contemporary cross-chain interoperability solutions are centralized and require re-engineering of the core blockchain stack to enable inter-communication and data sharing among heterogeneous blockchain networks. In this paper, we propose an application-based cross-chain interoperability solution named appXchain which allows blockchain networks of any architecture type and industrial focus to inter-communicate, share data, and make requests. Our solution utilizes the decentralized applications as a distributed translation layer that is capable of communicating and understanding multiple blockchain networks, thereby delegating requests and parameters among them. The architecture uses incentivized verifier nodes that maintain the integrity of shared data facilitating them to be readable by the entities of their network. We define and describe the roles and requirements of major entities of inter-operating blockchain networks in the context of healthcare. We present a detailed explanation of the sequence of interactions needed to share an Electronic Medical Record (EMR) document from one blockchain network to another along with the required algorithms. We implement the appXchain solution with Ethereum-based smart contracts for two hospitals and also present its cost and security analysis. We have made our smart contracts code and testing scripts publicly available.

NFTs for Open-Source and Commercial Software Licensing and Royalties

“…Phase 3 is similar to phase 2; however, the software developer chooses to list the distribution for 1.5 ETH, sets listing 1 as a dependency, and pays 0.3 ETH to the processors (trx [15][16]. For the weight estimation, four processors respond with an average of 33 (trx [17][18][19][20][21], and the developer rates three of them back (trx [22][23][24]. After the rating period passes, the fourth processors manually requests to unlock the account (trx 25).…”

“…A reputation system is a technique to keep track of the behavior of entities in the blockchain network. For example, the most common reputation system performance measurement lets users rate each other after finalizing a transaction [21].…”

Building operation and maintenance scheme based on sharding blockchain

“…The emergence of blockchain technology provides new means for solving the problems of data security and third-party trust faced by existing fields [ 28 ]. Once the concept of blockchain is proposed, it has attracted the attention of experts and researchers from all walks of life, and has been applied to finance [ 29 ], Industry 4.0 [ 30 ], electronic medical records [ 31 ] and other fields.…”

Wrapping Trust for Interoperability: A Preliminary Study of Wrapped Tokens

“…Risks and disadvantages do not only concern the chance of technology malfunction but also threats to the decentralization concept itself. Similarly, as to how oracles reintroduce the concept of trust and centralization in decentralized ecosystems [65], the issuance of tokens managed by centralized and trusted entities also undermines ecosystem decentralization [66]. Although pegged to the same value, the chance of having an untrusted copy of a trustless token should be considered when evaluating the advantages of interoperability obtained through wrapped tokens [67].…”