Economic Proof of Work

Blockchain is the distributed system allowing multiple parties to host a service. Nakamoto Consensus, also named Proof of Work (PoW), is widely used in Bitcoin and other blockchain systems. PoW is an important consensus algorithm. It solves the Byzantine Generals problem in an open network. It also protects the blockchain security from longest chain attack. World widely virtual currency mining was commonly regarded as over energy consuming. How to make use of the computation capacity provided by mining, is one of the most important problems to solve in blockchain. We extend Proof of Work to be useful and economic. And discover a simple method to generate the proof of storing useful data with PoW. In a blockchain based distributed file storage system, any storage resource owner could freely join as a service provider. It requires the service provider to show the proof of honestly keeping the data content, because the malicious provers may use other\u27s content to generate the proof in order to reduce their resource cost. This is out-sourcing attack. Furtherly, we proposed a novel technique to combine data replica process with Proof of Work\u27s contributing to blockchain security

Blockchain Technology

Blockchain came because of the occurrence of incredulity to single authorities by introducing the concept of network decentralization and data distribution saved in a ledger. Decentralization is used to validate discrepancies in the majority of data. The consensus mechanism collectively maintains the consistency of the ledger. A blockchain is a set of blocks containing transaction data interconnected to each other using the concept of cryptography. A mining process is an effort to add new blocks to the blockchain. The mining computer carries out the process after passing several complex mathematical problems. The fastest miner is rewarded with crypto coins. Some consensus mechanisms commonly used in blockchain are proof of work, proof of stake, practical byzantine fault tolerance, and proof of elapsed time. Blockchain network is designed and implemented in such a way that it can guarantee the security of its data, is easy to be audited, is robust to denial of service and majority attacks, and is private and confidential. The application of blockchain is not limited to finance systems; it can also be applied in health, education, supply chain, and state democracy systems

When Mobile Blockchain Meets Edge Computing

Blockchain, as the backbone technology of the current popular Bitcoin digital currency, has become a promising decentralized data management framework. Although blockchain has been widely adopted in many applications, e.g., finance, healthcare, and logistics, its application in mobile services is still limited. This is due to the fact that blockchain users need to solve preset proof-of-work puzzles to add new data, i.e., a block, to the blockchain. Solving the proof-of-work, however, consumes substantial resources in terms of CPU time and energy, which is not suitable for resource-limited mobile devices. To facilitate blockchain applications in future mobile Internet of Things systems, multiple access mobile edge computing appears to be an auspicious solution to solve the proof-of-work puzzles for mobile users. We first introduce a novel concept of edge computing for mobile blockchain. Then, we introduce an economic approach for edge computing resource management. Moreover, a prototype of mobile edge computing enabled blockchain systems is presented with experimental results to justify the proposed concept.Comment: Accepted by IEEE Communications Magazin