Handling Confidential Data on the Untrusted Cloud: An Agent-based Approach

Cloud computing allows shared computer and storage facilities to be used by a multitude of clients. While cloud management is centralized, the information resides in the cloud and information sharing can be implemented via off-the-shelf techniques for multiuser databases. Users, however, are very diffident for not having full control over their sensitive data. Untrusted database-as-a-server techniques are neither readily extendable to the cloud environment nor easily understandable by non-technical users. To solve this problem, we present an approach where agents share reserved data in a secure manner by the use of simple grant-and-revoke permissions on shared data.Comment: 7 pages, 9 figures, Cloud Computing 201

SoK: Cryptographically Protected Database Search

Protected database search systems cryptographically isolate the roles of reading from, writing to, and administering the database. This separation limits unnecessary administrator access and protects data in the case of system breaches. Since protected search was introduced in 2000, the area has grown rapidly; systems are offered by academia, start-ups, and established companies. However, there is no best protected search system or set of techniques. Design of such systems is a balancing act between security, functionality, performance, and usability. This challenge is made more difficult by ongoing database specialization, as some users will want the functionality of SQL, NoSQL, or NewSQL databases. This database evolution will continue, and the protected search community should be able to quickly provide functionality consistent with newly invented databases. At the same time, the community must accurately and clearly characterize the tradeoffs between different approaches. To address these challenges, we provide the following contributions: 1) An identification of the important primitive operations across database paradigms. We find there are a small number of base operations that can be used and combined to support a large number of database paradigms. 2) An evaluation of the current state of protected search systems in implementing these base operations. This evaluation describes the main approaches and tradeoffs for each base operation. Furthermore, it puts protected search in the context of unprotected search, identifying key gaps in functionality. 3) An analysis of attacks against protected search for different base queries. 4) A roadmap and tools for transforming a protected search system into a protected database, including an open-source performance evaluation platform and initial user opinions of protected search.Comment: 20 pages, to appear to IEEE Security and Privac

Function-specific schemes for verifiable computation

An integral component of modern computing is the ability to outsource data and computation to powerful remote servers, for instance, in the context of cloud computing or remote file storage. While participants can benefit from this interaction, a fundamental security issue that arises is that of integrity of computation: How can the end-user be certain that the result of a computation over the outsourced data has not been tampered with (not even by a compromised or adversarial server)? Cryptographic schemes for verifiable computation address this problem by accompanying each result with a proof that can be used to check the correctness of the performed computation. Recent advances in the field have led to the first implementations of schemes that can verify arbitrary computations. However, in practice the overhead of these general-purpose constructions remains prohibitive for most applications, with proof computation times (at the server) in the order of minutes or even hours for real-world problem instances. A different approach for designing such schemes targets specific types of computation and builds custom-made protocols, sacrificing generality for efficiency. An important representative of this function-specific approach is an authenticated data structure (ADS), where a specialized protocol is designed that supports query types associated with a particular outsourced dataset. This thesis presents three novel ADS constructions for the important query types of set operations, multi-dimensional range search, and pattern matching, and proves their security under cryptographic assumptions over bilinear groups. The scheme for set operations can support nested queries (e.g., two unions followed by an intersection of the results), extending previous works that only accommodate a single operation. The range search ADS provides an exponential (in the number of attributes in the dataset) asymptotic improvement from previous schemes for storage and computation costs. Finally, the pattern matching ADS supports text pattern and XML path queries with minimal cost, e.g., the overhead at the server is less than 4% compared to simply computing the result, for all our tested settings. The experimental evaluation of all three constructions shows significant improvements in proof-computation time over general-purpose schemes

The Internet's Effects on Global Production Networks: Challenges and Opportunities for Managing in Developing Asia

Placing global production networks (GPN) on the Internet poses a fundamental challenge, but also creates new opportunities for managing in Developing Asia. Network flagships can now select best-performing suppliers on a global scale, increasing the pressure on Asian suppliers. But the transition form EDI to the Internet may also provide new opportunities for Asian suppliers, by reducing barriers to network entry, and by enhancing knowledge diffusion. A conceptual framework is introduced to assess how the Internet reshapes business organization and GPN. That framework is applied to one of the role models of managing in Asia, Taiwan's Acer Group. The paper highlights a vicious circle that must be broken to reap the benefits of the Internet: Asian firms must reduce a huge efficiency gap between manufacturing and the management of supporting digital information systems (DIS). The challenge is to embrace the Internet as flexible infrastructures that support not only information exchange, but also knowledge sharing, creation and utilization. The Internet facilities this task: it provides new opportunities for the outsourcing of mission-critical support services.

Placing the Networks on the Web: Challenges and Opportunities for Managing in Developing Asia

Placing the networks on the Web poses a fundamental challenge, but also provides new opportunities for managing in Developing Asia. There is a huge efficiency gap between the region's manufacturing systems and the management of complementary, knowledge-intensive support services. The challenge is to reduce this gap as quickly as possible by embracing the Internet as a core business function, despite a weak base of accumulated knowledge of how to manage IT-based information systems. Asian companies, even the best, lag substantially behind their American and European counterparts. There is a potential vicious circle that needs to be broken: a belated transition to IT-based information systems has prevented the accumulation of knowledge, through trial-and-error, of how to design and implement an appropriate IT organization that reflects the peculiar strengths and weaknesses of diverse Asian management systems. Limited resources prevent any attempt to address these problems in a big leap forward. This implies that in-house efforts need to be supplemented with outsourcing of IT services. There is also a need for strategic partnering with major suppliers of Internet software and networking equipment. The opportunity is that the Internet provides almost unlimited opportunities for the outsourcing of mission-critical support services, such as ERP (enterprise resource planning), HRM (human resource management). Furthermore, fierce competition among major producers of Internet software and networking equipment has created a buyers' market - placing Asian firms in a reasonably strong bargaining position. These developments are generally not well covered by existing studies, which are primarily focused on developments in the U.S. and Europe. The paper tries to fill this gap, and explores how placing global production networks on the Web affects managing in Developing Asia. A conceptual framework is introduced in parts 1 to 3. That framework is then applied to one of the role models of managing in Asia, Taiwan's Acer Group. Part 1 introduces a taxonomy of expected benefits from Internet-enabled transformations of business organization. In part 2, we argue that the real issue is to analyze how the Internet reshapes the organization of global production networks. In part3, we access conflicting claims on how an increased use of the Internet to manage global production networks affects international knowledge diffusion. In part 4, the example of Taiwan's Acer Group is used to describe the challenge for Asian firms to embrace the Internet as a key management function. And in part 5, we ask what Acer's experience tells us about Developing Asia's opportunities.