International Journal on Cloud Computing: Services and Architecture (IJCCSA) Vol. 11, No. 1/2/3/4/5/6, December 2021 DOI: 10.5121/ijccsa.2021.11601 1 BLOCKCHAIN BASED DATA SECURITY AS A SERVICE IN CLOUD PLATFORM SECURITY Magesh Kasthuri Wipro Limited, Bengaluru, India ABSTRACT Blockchain is widely used for money related transaction and still there are many proven usecases across different industries like Retail in stock checks and order management, Manufacturing in good movement processing, Health care in patient database management to name a few. With this in mind, it is always important to understand the merits and demerits of both Public and Private Blockchain to understand their capabilities and limitations to decide which one is more suitable for an industry specific usecase implementation. In a Cloud based platform, data security plays a crucial role to cater to data protection and regulatory requirements and Blockchain can play an important role in this for accelerated workflow by providing ‘data security’ as a service capability. KEYWORDS Data Security, Blockchain, Cloud platforms, Data protection, Regulatory requirements 1. INTRODUCTION In PermissionLess Ledger, user can login anonymously without revealing the identity and controlling the transaction rate can be done through a defined owner group. On the other hand, Permissioned Ledger has defined roles like Owner, Approver, Viewer/Reader and Administrator. These roles has defined workflow activities and controlled transaction processing is ensured in a Permissioned Ledger based Blockchain platform using these user roles. There would be more than one users present for each role so that speed of transaction is faster as compared to PermissionLess Ledger. In a Multi-tenant cloud architecture, even the application environment is shared in a single workspace (subscription) there are restrictions to access the application and data (including the Virtual machines) and hence irrespective or public or private cloud environment, application and data security is ensured and contained within a limited group of known resources. Hence it is utmost important to have a robust data security service in cloud platform to accelerate workflow based resource access through some gatekeeper activities. 2. MULTI-TENANT APPLICATION DESIGN A multi-tenant design is a horizontal demarcation between application groups to restrict accessibility of application and data between user groups and security groups. In terms of multi- tenant database design solution, there are many options like design multiple database for each application or design a single shared database with multiple schemas so that schema level user permission can restrict data access between them or even have a single shared database with shared schema where table level permissions can isolate each tenants of application group.