مدل محافظت از حریم خصوصی: یک طرح جدید برای حسابرسی سهامداران ابری Privacy preserving model: a new scheme for auditing cloud stakeholders

Introduction Cloud computing is an emerging IT environment that has significantly transformed everyone’s vision of computing infrastructure, development models, and software distribution. Cloud computing is anticipated as the next generation high-tech paradigm for tomorrow’s promise [1]. It provides several utilities as revolutionary gigantic paradigms where clients can remotely store valuable and confidential information as to avail from on-demand high quality computing resources [2]. While data outsourcing reduces the burden on the cloud users (CUs) from local storage and management, it brings several open problems related to the security and privacy of customer’s outsourced data. On the other hand, cloud computing eradicates their physical control of data reliability and security, which can be addressed through the cooperation of three parties: the cloud service provider (CSP), the third party auditor (TPA) and the CU. Cloud computing has always been referred as virtualization of an existing server or data center. Subsequently, cloud computing is acknowledged as virtualization of existing data or data centers, providing multipurpose application support and enormous utility to remotely available users or clients [3]. This phenomenon leads to the cloud acting as a service, where services are provided upon request based on subscription or pay-peruse [4]. The cloud computing environment stores the valuable information and offers attractive user applications with reliable service support [5]. With the emergence of new technology, new categories of clouds and services are introduced such as supercomputing as service (SCaaS) and high-performance computing as a service (HPCaaS). From a security perspective, dealing with large amounts of data is a challenge. The security of CSPs has been investigated thoroughly from a storage standpoint [6–10]. Two highly sought CSP features that guarantee privacy protection are data availability and integrity. Since the CUs do not have physical access to the outsourced data, it raises the question of data privacy protection in cloud computing, particularly for users with very limited computing resources. Moreover, there are several other factors regarding the CSPs corruption that can deceitfully smash the CUs outsourced data [11]. For instance, a CSP can attempt to sustain its reputation by hiding the security incidents about the customer’s lost data [12]. Cloud services can be financially advantageous; however, there is no guarantee that the stored data will be secure and available at all times. If this continues to be an issue and is not thoroughly examined, the cloud computing environment may never reach its full potential. The massive amount of outsourced data, along with the CU’s limited resources, can present a daunting challenge for auditors when examining a cloud service [13]. One solution to this problem is to maintain a very low level of cloud storage overhead using minimal data retrieval operations. Although we face these challenges, it is still of utmost importance to develop trust between the CUs and CSPs.