(Received: 10-May-2020, Revised: 28-Jun.-2020 and 20-Jul.-2020 , Accepted: 8-Aug.-2020)
Blockchain is a revolutionary technology that gained widespread popularity since the emergence of crypto-currencies. The potential uses of Blockchain surpassed digital currency into a wider space that includes the Internet of Things (IoT), security applications and smart embedded systems, among others. As the number of Blockchain users increases, several drawbacks start to emerge, since Blockchains consume excessive amounts of energy to store and manipulate data. Furthermore, the limited scalability nature of Blockchains due to their massive storage requirements might become an issue. To improve the overall performance, several challenges in the current Blockchain structure should be tackled. This paper presents a hybrid system architecture that combines the distributed nature of Blockchains with the centralized feature of servers. Users will connect to servers via personal Blockchains, while servers will share a chain of Blockchains to ensure integrity and security. This will significantly decrease the storage requirements of end- users and enhance the scalability of networks. Businesses will highly benefit from this proposed structure, since it creates a reliable scalable business model.

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