IJSTE - International Journal of Science Technology & Engineering | Volume 6 | Issue 1 | July 2019 ISSN (online): 2349-784X All rights reserved by www.ijste.org 19 Blockchain: Benefits, Challenges & Applications in Different Domains Kaushik Das Anirban Patra UG Student UG Student Department of Computer Science & Engineering Department of Computer Science & Engineering Siliguri Institute of Technology, India Siliguri Institute of Technology, India Abstract Blockchain was born following the economic crisis of 2008 and as a solution to deal with the issues of the contemporary financial system. Based on research on crypto currencies, i.e., digitized currencies and operated by totally digital technologies, the Blockchain carries with it, according to the greatest technology gurus, new promises of innovation and innovation. The Blockchain is a revolutionary technology that allows the development and implementation of an "Internet of transactions". This paper provides an overview and the concept of blockchain and explains the benefits of blockchain and the challenges facing by the companies. Keywords: Blockchain, Blockchain applications, Benefits, Challenges blockchain ________________________________________________________________________________________________________ I. INTRODUCTION The idea of Blockchain [1] appeared with Bitcoin, the first cryptocurrency, known in the world, but, the channel shares common points with a cryptocurrency and the TCP / IP protocol. Historically the Internet and its TCP / IP ("Information Path") have accelerated the digital revolution, all thanks to the huge distribution of information in "peer-to-peer" PTP mode. In theory the Blockchain will produce "Transactional Paths" in PTP mode "peer-to-peer" is a duplicate register shared between all nodes of a network; each node can be a user or even a computer. To further simplify our purpose, this famous register notifies and timestamps each exchange between each node in a "block". As soon as the "block" is filled, it is "chained" after the previous blocks, so that everything is inscribed and visible to all in the network. It is therefore both a timestamped, secure server and a secure peer-to-peer database and that is where the disruption of classical transactional models as we know them lies. In every organizations, a trusted third ensures and guarantee that a transaction has taken place, and that it is operated only one times (bank, notary, auditor etc.). Blockchain allows a transaction or an exchange to take place between several "parties" by avoiding the presence of the trusted third party. In blockchain,the blocks are stacked chronologically, timestamped, and encrypted, the whole having been "validated" by the "miners" (through one of the nodes of the network) who make available their computing power in order to solve the mathematical problem submitted by the "chain of blocks". The resolution of the problem is thus equivalent to "validating" the transaction, much like a clearing house for payments and since transactions are visible to all, Blockchain is transformed into a formidable audit tool, which helps to build trust among the players. II. BLOCKCHAIN BENEFITS Traceability and Transparency Traceability is ensured (audit trail) in Blockchain as all transactions are permanently registered, For example, Walmart, a company that uses Blockchain technology to improve and ensure the traceability of its products allows to have a visual access to immediate and certified information on the stages of production, distribution and marketing of its products. Security It is with the use of the cryptographic approach, the Blockchain ensures with great precision the security of the transactions. In addition, information networking ensures that transactions cannot be hacked. Identity theft when carrying out a transaction is therefore theoretically no longer possible. Timeliness Due to Blockchain’s networked infrastructure, registration and access to informati on are almost instantaneous. As proof, the world of finance is currently using the Blockchain approach to facilitate intermediation between banks, clearing houses and central banks. They see the opportunity to increase the efficiency of operations: speed of execution, reduction of resources and costs.