Attention:The NSF Public Access Repository (PAR) system and access will be unavailable from 11:00 PM ET on Thursday, August 13 until 12:00 AM ET on Friday, August 14 due to maintenance. We apologize for the inconvenience.

Explore Research Products in the PAR
It may take a few hours for recently added research products to appear in PAR search results.


Title: A Wake-up Call: Managing Data in an Untrusted World
Once upon a time databases were structured, one size fitted all and they resided on machines that were trustworthy and even when they failed, they simply crashed. This era has come and gone as eloquently stated by Stonebraker and Cetintemel [16]. We now have key-value stores, graph databases, text databases, and a myriad of unstructured data repositories. The database community has wholeheartedly accepted the fact that the same information might come in different formats, modes and representations. We also accept that data might not be ”clean” and that data might need to be ”cleaned” due to the diverse sources of information. However, we, as a database community still cling to our 20th century belief that databases always reside on trustworthy, honest servers. Although the database community has always considered fault-tolerance as an integral building block of data management (remember ”D” in ACID is for Durability), we still have trouble accepting the fact that not all failures are simply crash failures and might in fact involve malicious and non-trustworthy infrastructure. This notion has been challenged and abandoned by many other Computer Science communities, most notably the security and the distributed systems communities. The rise of the cloud computing paradigm as well as the rapid popularity of blockchains demand a rethinking of our na¨ıve, comfortable beliefs in an ideal benign infrastructure. In the cloud, clients store their sensitive data in remote servers owned and operated by cloud providers. The Security and Crypto Communities have made significant inroads to protect both data and access privacy from malicious untrusted storage providers using encryption and oblivious data stores. The Distributed Systems and the Systems Communities have developed consensus protocols to ensure the fault-tolerant maintenance of data residing on untrusted, malicious infrastructure. However, these solutions face significant scalability and performance challenges when incorporated in large scale data repositories. Novel database designs need to directly address the natural tension between performance, fault-tolerance and trustworthiness. This is a perfect setting for the database community to lead and guide.  more » « less
Award ID(s):
1703560
PAR ID:
10238785
Author(s) / Creator(s):
;
Editor(s):
Wang, H.
Date Published:
Journal Name:
IEEE bulletin
Volume:
43
Issue:
2
ISSN:
0162-3842
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
More Like this
  1. ; ; ; ; (, Advances in Databases and Information Systems)
    Darmont, J; Novikov, B.; Wrembel, R. (Ed.)
    Bitcoin [12] is a successful and interesting example of a global scale peer-to-peer cryptocurrency that integrates many techniques and protocols from cryptography, distributed systems, and databases. The main underlying data structure is blockchain, a scalable fully replicated structure that is shared among all participants and guarantees a consistent view of all user transactions by all participants in the system. In a blockchain, nodes agree on their shared states across a large network of untrusted participants. Although originally devised for cryptocurrencies, recent systems exploit its many unique features such as transparency, provenance, fault tolerance, and authenticity to support a wide range of distributed applications. Bitcoin and other cryptocurrencies use permissionless blockchains. In a permissionless blockchain, the network is public, and anyone can participate without a specific identity. Many other distributed applications, such as supply chain management and healthcare, are deployed on permissioned blockchains consisting of a set of known, identified nodes that still might not fully trust each other. This paper illustrates some of the main challenges and opportunities from a database perspective in the many novel and interesting application domains of blockchains. These opportunities are illustrated using various examples from recent research in both permissionless and permissioned blockchains. Two main themes unite the various examples: (1) the important role of distribution and consensus in managing large scale systems and (2) the need to tolerate malicious failures. The advent of cloud computing and large data centers shifted large scale data management infrastructures from centralized databases to distributed systems. One of the main challenges in designing distributed systems is the need for fault-tolerance. Cloud-based systems typically assume trusted infrastructures, since data centers are owned by the enterprises managing the data, and hence the design typically only assumes and tolerates crash failures. The advent of blockchain and the underlying premise that copies of the blockchain are distributed among untrusted entities has shifted the focus of fault-tolerance from tolerating crash failures to tolerating malicious failures. These interesting and challenging settings pose great opportunities for database researchers. 
    more » « less
  2. ; ; ; ; (, Proceedings of the 21th International Conference on Extending Database Technology, EDBT 2018)
    Although outsourcing data to cloud storage has become popular, the increasing concerns about data security and privacy in the cloud blocks broader cloud adoption. Recent efforts have developed oblivious storage systems to hide both the data content and the data access patterns from an untrusted cloud provider. These systems have shown great progress in improving the efficiency of oblivious accesses. However, these systems mainly focus on privacy without considering fault-tolerance of different system components. This makes prior proposals impractical for cloud applications that require 24/7 availability. In this demonstration, we propose Pharos, the Privacy Hazards of Replicating ORAM Stores. We aim to highlight the data access pattern privacy hazards of naively applying common database replication and operation execution techniques such as locking and asymmetric quorums. 
    more » « less
  3. ; ; ; (, IEEE International Conference on Distributed Computing Systems)
    null (Ed.)
    Significant amounts of data are currently being stored and managed on third-party servers. It is impractical for many small scale enterprises to own their private datacenters, hence renting third-party servers is a viable solution for such businesses. But the increasing number of malicious attacks, both internal and external, as well as buggy software on third-party servers is causing clients to loose their trust in these external infrastructures. While small enterprises cannot avoid using external infrastructures, they need the right set of protocols to manage their data on untrusted infrastructures. In this paper, we propose TFCommit, a novel atomic commitment protocol that executes transactions on data stored across multiple untrusted servers. To our knowledge, TFCommit is the first atomic commitment protocol to execute transactions in an untrusted environment without using expensive Byzantine replication. Using TFCommit, we propose an auditable data management system, Fides, residing completely on untrustworthy infrastructure. As an auditable system, Fides guarantees the detection of potentially malicious failures occurring on untrusted servers using tamper-resistant logs with the support of cryptographic techniques. The experimental evaluation demonstrates the scalability of our approach and the relatively low overhead of executing transactions on untrusted infrastructure. 
    more » « less
  4. ; ; ; ; ; ; ; (, Proceedings of the ACM on Programming Languages)
    Confidential computing (CC), designed for security-critical scenarios, uses remote attestation to guarantee code integrity on cloud servers. However, CC alone cannot provide assurance of high-level security properties (e.g., no data leak) on the code. In this paper, we introduce a novel framework, Agora, scrupulously designed to provide a trustworthy and open verification platform for CC. To prompt trustworthiness, we observe that certain verification tasks can be delegated to untrusted entities, while the corresponding (smaller) validators are securely housed within the trusted computing base (TCB). Moreover, through a novel blockchain-based bounty task manager, it also utilizes crowdsourcing to remove trust in complex theorem provers. These synergistic techniques successfully ameliorate the TCB size burden associated with two procedures: binary analysis and theorem proving. To prompt openness, Agora supports a versatile assertion language that allows verification of various security policies. Moreover, the design of Agora enables untrusted parties to participate in any complex processes out of Agora’s TCB. By implementing verification workflows for software-based fault isolation, information flow control, and side-channel mitigation policies, our evaluation demonstrates the efficacy of Agora. 
    more » « less
  5. ; ; (, IEEE)
    We show that it is possible to achieve information theoretic location privacy for secondary users (SUs) in database-driven cognitive radio networks (CRNs) with an end-to-end delay less than a second, which is significantly better than that of the existing alternatives offering only a computational privacy. This is achieved based on a keen observation that, by the requirement of Federal Communications Commission (FCC), all certified spectrum databases synchronize their records. Hence, the same copy of spectrum database is available through multiple (distinct) providers. We harness the synergy between multi-server private information retrieval (PIR) and database-driven CRN architecture to offer an optimal level of privacy with high efficiency by exploiting this observation. We demonstrated, analytically and experimentally with deployments on actual cloud systems that, our adaptations of multi-server PIR outperform that of the (currently) fastest single-server PIR by a magnitude of times with information-theoretic security, collusion resiliency, and fault-tolerance features. Our analysis indicates that multi-server PIR is an ideal cryptographic tool to provide location privacy in database-driven CRNs, in which the requirement of replicated databases is a natural part of the system architecture, and therefore SUs can enjoy all advantages of multi-server PIR without any additional architectural and deployment costs. 
    more » « less
  • Citation Formats
  • MLA
  • APA
  • Chicago
  • BibTeX
  • Text Encoded Conversion
  • XML
  • Save / Share this Record
  • Send to Email