System for Cooperative Query Answer Authentication in Cloud over Anonymous Data

Abstract

In data publishing model, owner of data outsource the data to a third party publisher which are Cloud Service Providers (CSP) who satisfies the data requirement of the end user on behalf of actual data owner. But the cloud service provider may be untrustworthy or system may lack in security. So there need to be a way for user to check the answers received from cloud whether it is same as data owner would have send. In this paper we proposed a system for authenticating query answers send from cloud service providers. This system is based on three concepts ring signature, Merkel Hash Tree (MHT) and non-repudiable service protocol using online trusted authority (TA). These techniques work in cooperation with each other to provide user correct answer for his submitted query. The nonrepudiation protocol protects user and CSP from each other's malicious trading behavior.