Blockchain technology is the first successful Bitcoin Network. It enables the ledger to become more decentralized and secure. Since it is not limited to bitcoin and controlled by third parties by government, corporations, or banks, the technology is capturing several industries, including cryptocurrency, infrastructure& hardware, financial technology, Internet & mobile and so on. Blockchain is used as a public ledger to verify all peer-to-peer system transactions and maintain traded bitcoin spending from central authorities while bitcoin has distributed transactions. Achieving high Blockchain-based performance and privacy & security are global issues that are desire to be overcome as claims show they are still significant challenges in many Blockchain applications. This paper presents an introduction to Blockchain and the process of this technology in the way of outlining Blockchain types. Also, recent advances, challenges, real economy integration, and current situations of this technology have been listed.

Distributed ledger technologies have attracted significant attention recently and blockchain, as the underlying technology of cryptocurrencies, is the focal point of this attention. Blockchain has been used in various domains, such as cloud, fog, and edge computing and Internet of Things (IoT). However, it faces some limitations and lacks the capability to support frequent transactions. On the other side, after cloud and fog computing, edge computing serves as a key enabler for many future technologies like 5G, IoT, and vehicle-to-vehicle communications by connecting cloud computing resources and services to the end users and extends them at the edge of the network, but it currently confronts with challenges in decentralized management and security. Incorporating of blockchain and edge computing in one system can provide reliable access and control of the network, storage and computation distributed at the edges, thus providing a large scale of network servers, data storage and validity computation near the end in a secure manner. Notwithstanding the benefits of integrated blockchain and edge computing systems, their scalability enhancement, self-organization, resource management, functions integration and security issues need to be addressed before widespread implementation. This paper reviews some of the studies about enabling the integrated blockchain and edge computing system. Several critical aspects of the integration of blockchain and edge computing are identified. Finally, some of the effects of this integration on the business are discussed.

Dear Editor, Nowadays, healthcare has been faced with different technologies that promise new advantages for better and more advanced healthcare. Blockchain is taken into consideration as one of the emerging technologies, which there are great interesting. According to Gartner, blockchain is classified as one of the top ten strategic technology trends in 2020. 1 In current systems, a thirdparty control the transaction between requester and provider. For example, in the internet-based purchasing, the bank controls the financial transaction between customer and seller. In other words, there is a centralized control on the transactions, and consequently, the data is stored in the centralized database...

Medical drones are used to transport medical supplies, equipment, and personnel to remote and underserved areas, providing life-saving assistance to communities in need. However, the current system of medical supply chains is often inefficient and prone to errors, with little transparency and accountability. By incorporating blockchain technology into the medical drone system, it is possible to improve the transparency and security of medical supply chains, as well as the tracking and monitoring of medical drones. Blockchain can be used to securely store and manage information about medical drone deliveries, including the origin and destination of the drones, as well as the type and quantity of medical supplies being transported. Additionally, blockchain can also be used to manage payments for medical drone services, ensuring that payments are securely and transparently processed, tracking the maintenance and repair of medical drones, and ensuring that they are in good condition and safe to use. In conclusion, the implementation of medical drones using blockchain technology has the potential to greatly improve the efficiency, security, and transparency of medical supply chains. This can help to ensure that medical supplies and equipment reach their intended destination.

Background and Objectives: Blockchain technology as a distributed and tamper-proof data ledger is attracting more and more attention from various fields around the world. Due to the continuously growing of the blockchain in both transaction data and the number of nodes joining the network, scalability emerges as a challenging issue. Methods: In this survey, the existing scalability solutions in the blockchain are discussed under five categories including on-chain scalability, off-chain scalability, scalable consensus mechanisms, DAG-based scalability, and horizontal scalability through sharding. Meanwhile, the novelties they have created on the fundamental layers of the blockchain architecture are investigated.Results: As a result, the advantages and disadvantages of the discussed mechanisms are pointed out, and a comparison between them in terms of different scalability metrics such as throughput, latency, bandwidth, and storage usage is presented. Therefore, this study provides a comprehensive understanding of the various aspects of blockchain scalability and the available scalability solutions. Finally, the research directions and open issues in each category are argued to motivate further improvement efforts for blockchain scalability in the future.Conclusion: Scalability allows blockchain system to sustain its performance as it grows up. Lack of scalability has a negative effect on the mass adoption of the blockchain in practical environments. This paper presents a profound analysis of the existing scalability solutions, the issues and challenges they address, and the ones that are not resolved yet. Consequently, it inspires novel ideas for more scalable and efficient blockchains in the future.