IJRET: International Journal of Research in Engineering and Technology eISSN: 2319-1163 | pISSN: 2321-7308 __________________________________________________________________________________________ Volume: 03 Special Issue: 03 | May-2014 | NCRIET-2014, Available @ http://www.ijret.org 403 NoSQL DATABASES: NEW MILLENNIUM DATABASE FOR BIG DATA, BIG USERS, CLOUD COMPUTING AND ITS SECURITY CHALLENGES Asadulla Khan Zaki Student, Department of Computer Science and Engineering, BMS College of Engineering, Bangalore, India Abstract The field of databases has emerged in last decades of years. New architectures try to meet the need to store more and more various kinds of diverse data. The current trend of Big Data(too diverse data, unstructured data, semi-structured data, fast changing data), Big Users(global users 24 hours a day, 365 days a year) and Cloud Computing(new applications use a three-tier internet architecture, run in a public or private cloud) are the driving force for the organizations to migrate towards Non-Relational databases(referring as NoSQL popularly called as “NOT ONLY SQL”)from Relational Databases. The main market of Relational Databases is business data processing and these databases are architected to run a single machine and uses a rigid and scheme- based approach to modeling the data and dealing with Big Data and global users on a cloud environment becomes more and more difficult with relational databases. Non-relational databases (NoSQL databases) are considering as new Era database, it provides dynamic schemas, flexible data model, scale-out architecture, efficient big data storage and access requirement. Today the use of NoSQL is mainly due to its Scalability and Performance characteristics. Only a few years ago the Scalability and Performance were not such a big problem but the huge amount of data that is collected today is infinitely much more than ten years ago and also the growth of cloud computing results in large data store even more. This paper includes the introduction, causes of migrating towards NoSQL databases, characteristics, classification of NoSQL databases. Finally the security issues in NoSQL Databases are described and the security enforcement mechanism is proposed. Keywords: NoSQL, Big Data, Big Users, Key-value store, RDBMS, Security -----------------------------------------------------------------------***----------------------------------------------------------------------- 1. INTRODUCTION Today, there exist many different types of databases, not only the traditional relational databases but several other architectures designed to handle different types of data. Since the 70s the relational model was the dominant, with the implementations like Oracle database, MySQL and Microsoft SQL Servers and almost all databases followed the same basic architecture. At the beginning of the new millennium, developers started to realize that their data did not fit for the relational model and some of them started to develop other architectures for storing data in databases. When choosing a database today the problem is much more complex to decide the best architecture for data storage and retrieval of data. [1] Building of applications is now continuously changing.In decade of 90’, web companies come up with the scaling features in various dimensions of applications due to the following factors [2]:  The increase in number of concurrent global users access the applications via web and mobile devices, these users are popularly known as big users.  The huge volume of data is getting collected and processed today, and it becomes mandatory to collect various kinds of structured and unstructured data and its use became an integral part and it adds richness to applications, popularly known as big data.  Today, with the emergence of cloud, applications use a three-tier internet architecture that run in a public or private cloud that support big users and big data. Dealing with big users and big data using relational database technology becomes more and more difficult. The main reason is that relational databases depend on static schemas, and a rigid approach toward modeling the data. Google, Amazon, Facebook, and Linkedln are among the first companies to discover the serious limitations of relational database technology for supporting big data and big user’s requirements. To overcome these limitations, these companies brought up with new data management techniques, their initiatives results in producing a large interest among several developing companies that werefacing the related problems. As a result, a new database is designed with novel data management model called as NoSQL (populary called as ―Not Only SQL‖). Today, the NoSQL databases are rapidly growing and deploying in many internet companies and other enterprises. It’s gradually considered as a feasiblechoice when compared to relational databases, especially, more organizations identify that, the performance and scalability