Watermarking Databases

Security of Data stored in a database is an important measure of trust when database as a service paradigm is considered. In today’s internet based applications and online storage systems the database service providers should implement proper privacy measures and take stringent actions against attacks and secure customers’ valuable data. In this paper, we anticipate the present day situations and attacks and suggest watermarking as a solution to achieve security against forgery and theft of databases. We give a brief account of audio, video, text and image water marking techniques. We identify important attacks in this sector and study their modus operandi. Our study also gives a survey about some of the past work and robust watermarking algorithms for relational databases and their advantages. Considering the present day importance of security we propose a two tier model for watermarking of databases. The two tier model watermarks a database as a whole along with the individual data objects stored in it. Keywords—Database as a service, Fingerprinting, Histogram, Relational databases, Watermarking Introduction Data are one of the main assets of each organization, from the smallest company to international corporations. In this respect, a new emerging option is represented by the Database as a Service (DBAAS) paradigm. The market for this kind of solution has attracted the interests of many vendors, from IBM and Microsoft, to small innovators. One of the most serious obstacles to the widespread use of DBAAS is related to security [1] [2]. The internet has become a part of lives today. Various multimedia objects are stored in central archive or distributed over various heterogeneous database servers interconnected by a broadband network. Online Learning, Online Healthcare transactions, online user databases and accounts: are some of the examples. Today’s database is prone to threats of all kinds. These may include categories like Disclosure – Snooping, Trojan Horses. Deception – Modification, spoofing, repudiation of origin, denial of receipt, Disruption – Modification, Usurpation – Modification, spoofing, delay, denial of service. So the goals of security can be classified into three basic classes as below. Prevention – Prevent attackers from violating security policy, Detection – Detect attackers’ violation of security policy and Recovery – Stop attack, assess and repair damage and continue to function correctly even if attack succeeds. Industry is making significant investments to deliver digital audio, image, and video information to consumers and customers. A new infrastructure of digital audio, image, and video recorders and players, on-line services, and electronic commerce is rapidly being deployed. For the security of such a large database system we are going to focus on the concept of watermarking in databases to provide security and copyright policies. In particular, it is possible to hide data (information) within digital audio, image, and video files. The information is hidden in the sense that it is perceptually and statistically undetectable. With many schemes, the hidden information can still be recovered if the host signal is compressed, edited, or converted from digital to analog format and back. Watermarking embeds the data into original data object like image, audio or video file. This data can be used for following purposes [1] [2]. 1. As an information for copyright protections and knowing about the creator of the file. 2. Encryption of data can be done before hiding. Such encrypted data can be beneficial to support non repudiation. 3. Access control information for a file can be embedded as a watermark in it. 4. Metadata can be embedded into file using a watermark. The focus of this paper is to study and review existing relational database watermarking schemes