Selective and Private Access to Outsourced Data Centers

Abstract

The advancements in the Information Technology and the rapid diffusion of novel computing paradigms have accelerated the trend of moving data to the cloud. Public and private organizations are more often outsourcing their data centers to the cloud for economic and/or performance reasons, thus making data confidentiality an essential requirement. A basic technique for protecting data confidentiality relies on encryption: data are encrypted by the owner before their outsourcing. Encryption however complicates both the query evaluation and enforcement of access restrictions to outsourced data. In this chapter, we provide an overview of the issues and techniques related to the support of selective and private access to outsourced data in a scenario where the cloud provider is trusted for managing the data but not for reading their content. We therefore illustrate methods for enforcing access control and for efficiently and privately executing queries (at the server side) over encrypted data. We also show how the combined adoption of approaches supporting access control and for efficient query evaluation may cause novel privacy issues that need to be carefully handled.

Protecting Resources and Regulating Access in Cloud-Based Object Storage

“…The main disadvantages are that the data owner has to directly manage the encryption keys and has to enforce access control restrictions as well as changes in the access control policy. In this scenario, access control can be enforced using an approach based on selective encryption [12]. Intuitively, selective encryption means that the data owner encrypts different portions of her data using different keys and discloses to each user only the encryption keys used to protect the data they can access.…”

“…Encryption is at the basis of many of these techniques: when data are encrypted they are visible only to the users who know the encryption key. Encryption has then been adopted not only as a valid solution for protecting data confidentiality (even against adversaries with access to the physical representation of the data, including the cloud providers themselves), but also for supporting selective sharing of such data [12]. In this case, CSP data owner CSP CSP users Fig.…”