Analysis of Security and Privacy Aspects of Blockchain Technologies from Smart Era' Perspective: The Challenges and a Way Forward to Future

Abstract

In 2008–2009, a distributed technology “blockchain” was introduced in cryptocurrency (as Bitcoin). Blockchain is a distributed consensus scheme which allows any transactions or any other data, and stores it securely with verifying by peer users (users available in a network), i.e. without the need of any centralized authority (CA). The blockchain concept is purely distributed and decentralized in nature, and is receiving attraction from many areas and sectors (for protecting data or providing reliable communications). Initially, Bitcoin (a popular cryptocurrency) used well-known proof of work hash-based mechanism to make respective Bitcoin (a cryptocurrency) more foolproof. Blockchain provides different functional and security guarantees, so it can bring more change to a large number of systems and businesses (or applications). In general, essential building blocks of blockchain security has decentralization structure, security by block, and encryption via consensus mechanisms or proof of work—but due to lot of popularity of this technology among many applications, several serious issues like security and privacy are raised in this technology. Security and privacy are general problems in blockchain technology of today’s era (raised in every computing environment). Scalability, security, privacy, and sustainability are essential issues in blockchain technology. The future world requires distributed trust and everything in distributed form, including security and privacy issues and the need to provide a state of art work (for each available technology or application). Our work will be more useful to academia and the blockchain community to do some innovative work to solve complex problems and to improve industries and businesses productivity. Among all existing technologies (in communication), blockchain technology guarantees more reliable and expedient services. In blockchain technology, it is important to consider the security and privacy issues and challenges behind the innovative technology. In this chapter, we provide a complete introduction of blockchain and its uses in several applications, analyzing problems by deploying newer cryptographic techniques and mechanisms to enabling use cases like privacy, preserving file storage, and security of user information. Also, several research gaps, as well as the challenges and opportunities in blockchain technology, are discussed. In summary, we provide comprehensive flow regarding blockchain technology which has not been provided yet by anyone. In this chapter, challenges and opportunities from the prospective of security and privacy of data in blockchain will be discussed (with respect to the security and privacy community point of view). Furthermore, we will provide some future trends which blockchain technology may adapt in near future (in brief).