Security, Privacy, and Digital Forensics in the Cloud

3Confidentiality of Data in the Cloud: Conflicts Between Security and Cost

Nathalie Baracaldo¹ and Joseph Glider²

¹ IBM Almaden Research Center, San Jose, CA, USA

² SAP Labs, Palo Alto, CA, USA

3.1 Introduction

Data confidentiality has been and remains a large concern for online and especially cloud‐resident data. Information, once naturally protected by limited or no network connectivity outside of the information owner's domain, is now potentially vulnerable to theft or corruption resulting from any of a growing set of possible attacks. This chapter describes the trends of the last 20 years that have increased data‐confidentiality concerns, technologies that have been used to address these concerns, conflicts between those technologies and the cost‐reduction measures that cloud providers put in place, and some possible approaches to reconciling the confidentiality technologies with cost‐reducing features.

Section 3.2 of this chapter presents some background on cloud storage systems and reasons data‐confidentiality concerns have grown over the past 20 years. Then, Section 3.3 discusses concrete confidentiality issues and adversaries of cloud storage systems. Section 3.4 presents some common techniques used to protect confidentiality in current cloud storage systems, and Section 3.5 shows why these protection techniques often conflict with data‐reduction methods, resulting in an increase of costs. Then, Sections 3.6 and 3.7 provide an overview and comparison of potential solutions ...