International Research Journal of Engineering and Technology (IRJET) e-ISSN: 2395-0056 Volume: 07 Issue: 06 | June 2020 www.irjet.net p-ISSN: 2395-0072 © 2020, IRJET | Impact Factor value: 7.529 | ISO 9001:2008 Certified Journal | Page 2498 Survey of Traditional and Blockchain-based EHR system Miss Falguni Pawar 1 , Prof. Viresh Vanarote 2 1 T.E Computer Engineering, RMD School of Engineering, Warje, Pune-58, Maharashtra, India 2 Asst. Prof. of Computer Engineering, RMD School of Engineering, Warje, Pune-58, Maharashtra, India ---------------------------------------------------------------------***--------------------------------------------------------------------- Abstract - The gradual transformation of healthcare systems from paper-based records to electronic records has its own advantages like easy access to medical data, able to maintain effective clinical workflows, reduced medical costs, lowers medical errors, easy exchange of data between various stakeholders, but this transition also came with some unique challenges with respect to privacy, confidentiality, and security of medical information of the patients. These electronic health records of the patient are comprised of a wide variety of data, such as medical histories, demographics, medication, immunization status, laboratory test reports, and other sensitive patient information. The existing cryptographic and non-cryptographic approaches were used to address these challenges to some extent but not completely solve the problems. This paper discusses an overview of e-Health System, cryptographic and non-cryptographic approaches, their drawbacks, and a new electronic health record system using Blockchain technology which makes it difficult for the hackers to change, hack or cheat the system. Keywords: e-Health, Electronic Health Record(EHR), Cryptography, Cloud Computing, Encryption and Decryption Motivation: The existing privacy-preserving mechanisms are not enough powerful to ensure foolproof security in the e-health cloud. Contrary to most beliefs, the main risk faced by health records hosted in cloud servers is internal attacks from people who have authorized credentials to access data within organizations, where database administrators or key managers are attackers, which is significantly worse than the external attacks. This paper aims to provide a proper understanding of concepts of privacy-preserving mechanisms and also reviews some of its drawbacks in e- healthcare environments that make electronic health records vulnerable to threats in the cloud arena. E-health data contains various sensitive and confidential information ranging from patient data to financial information including social security number, credit card details, whose leakage not only throws open sensitive patients’ information and cause financial losses but also breaks the most fundamental right of a citizen in any country i.e. right to privacy. Even though we have made access to EHR easier for patients and healthcare professionals there are some issues like Data encryption, secure storage, authentication, access control, key management, efficient user revocation, etc. which are yet to be addressed and resolved. 1. Introduction The digital technology of the 21st century has changed the complete picture of the healthcare system across the world. Transitioning to an e-health solution provides high efficiency and flexibility to healthcare services by providing a platform that allows the easy share of healthcare data among different stakeholders, convenient storage of medical information. Cloud computing allows the creation, storage, and retrieval of healthcare information by all healthcare providers, doctors, and patients. Third-party cloud services provide immense benefits in terms of cost-effective storage, access, processing, and updating of information but these huge databases are operated as a single ecosystem that can be accessed by different users from multiple locations, it is susceptible to intrusion and thus posing a threat to patient's data in the cloud. Therefore, having medical data on the third-party servers naturally increase these vulnerabilities. Healthcare cyber threats is a major concern for two main reasons:  In addition to the medical information of the patient it also has valuable financial data.  Since there are very few people who do not see healthcare providers, nearly everyone’s personal information is available in some form which makes it more vulnerable to identity theft. After reviewing the numerous research paper about the privacy-preserving mechanism of e-health solutions we have identified the following tasks 1. Overview of the e-health system in the cloud 2. Cryptographic and Non-cryptographic approaches to protect e-health data and their drawbacks 3. Overview of blockchain technology 4. Patient-Centric EHR system using blockchain technology 2. Literature Survey [1] A systematic and complete review of security and privacy-preserving challenges in e-health solutions indicates various privacy-preserving approaches to ensure the privacy and security of electronic health records (EHRs) in the cloud. [2] In this paper, Authors have investigated privacy in eHealth as a communication problem, since future eHealth