Data outsourcing and transaction security in cloud environment

Abstract

Cloud computing is one of the prominent areas in today s world. It is used to deliver the computing services such as networking, software etc over the Internet. There are several advantages that exist in cloud computing but the major drawback is that it is difficult to build a secure cloud storage system. Additionally, cloud environment are controlled by several service providers who are semi- trusted, and also hackers are possible to attack the service providers easily without the knowledge of the owner. Cloud environment provides security depending upon the centralized third party provider and hence the data confidentiality has to be compromised. Data confidentiality and integrity are the key terms of security and privacy. Data confidentiality represents to keep the sensitive data secure. Data integrity provides assurance to the information which is mainly used to improve the privacy of the data. Data confidentiality can be assured by using cryptographic method. There are many cryptographic methods available, but every algorithm has its drawbacks in terms of time complexity, various attacks, etc. The thesis commences with the construction of a secure cloud storage system in a decentralized way. Though service providers are there, the data owner holds full control over the data. Without the awareness of the data owner, the service provider cannot access the data. Users who want to retrieve the file send the request to the cloud service provider. The cloud service provider retrieves the file only with the knowledge of the data owner. The data owner is the deciding authority as to with whom the data can be shared. If the data owner is offline, then through notification system such as SMS, the cloud service provider sends the request to data owner in order to retrieve the file. newline newline newline