Query: blockchain SGX

title: A Distributed Oracle Using Intel SGX for Blockchain Based IoT Applications
abstract: A blockchain oracle problem is a problem that defines a mechanism for how to safely bring external data to the blockchain. Although there have been various research efforts to solve this problem, existing solutions are limited in that they do not support either data availability or data integrity. Furthermore, no solution has been proposed to minimize the response time when an oracle server is malicious or overloaded. This paper proposes a distributed oracle using Intel Software Guard Extensions (SGX) The proposed approach uses multiple oracle servers to support data availability. It also supports data integrity using Intel SGX and Transport Layer Security (TLS) communication. The reputation system, which favors oracle servers with short response times, minimizes the average response time even if some of the oracle servers are malicious. The benchmarking results show that the response time of the proposed approach with 3 oracle servers is only 14% slower than a centralized oracle called Town crier and scales well even if the number of oracle servers is increased up to 9. The reputation system is also evaluated, and its feasibility is analyzed using various experiments.

title: When Blockchain Meets SGX: An Overview, Challenges, and Open Issues
abstract: As a decentralized, public, and digital ledger technology in Peer to Peer network, blockchain has received much attention from various fields, including finance, healthcare, supply chain, etc. However, some challenges (e.g. scalability, privacy, and security issues) severely affects the wide adoption of blockchain technology. Recently, Intel software guard extensions (SGX) as new trusted computing technologies, have provided a new solution to the above challenges in the blockchain area. Although many studies have focused on using SGX technology to enhance their schemes in the blockchain areas, no comprehensive survey has systematically analyzed and delineated these studies. This article is the first to systematically discuss the application status of SGX in the blockchain area. In this article, we study the scheme designs, advantages, and disadvantages of the existing works using a six layer hierarchical structure of the blockchain. We also summarize the functions of SGX and formally analyze the advantages and disadvantages of SGX. Finally, we review the remaining challenges and present a list of possible directions for future research.

title: Authenticated Range Query Using SGX for Blockchain Light Clients
abstract: Due to limited computing and storage resources, light clients and full nodes coexist in a typical blockchain system. Any query from light clients must be forwarded to full nodes for execution, and light clients verify the integrity of query results returned. Since existing authenticated query based on Authenticated Data Structure (ADS) suffers from significant network, storage and computing overheads by virtue of Verification Objects (VO) an alternative way turns to Trust Execution Environment (TEE) with which light clients have no need to receive or verify any VO. However, state of the art TEE cannot deal with large scale application conveniently due to limited secure memory space (i.e, the size of enclave in Intel SGX is only 128MB) Hence, we organize data hierarchically in both trusted (enclave) and untrusted memory and only buffer hot data in enclave to reduce page swapping overhead between two kinds of memory. Security analysis and empirical study validate the effectiveness of our proposed solutions.

title: AuthQX: Enabling Authenticated Query over Blockchain via Intel SGX
abstract: With the popularization of blockchain technology in traditional industries, though the desire for supporting various authenticated queries becomes more urgent, current blockchain platforms cannot offer sufficient means of achieving authenticated query for light clients, because Authenticated Data Structure (ADS) suffers from performance issues and state of the art Trust Execution Environment (TEE) cannot deal with large scale applications conveniently due to limited secure memory. In this study, we present a new query authentication scheme, named AuthQX, leveraging the commonly available trusted environment of Intel SGX. AuthQX organizes data hierarchically in trusted SGX enclave and untrusted memory to implement authenticated query cheaply.

title: Bottom up: A SGX based Blockchain Trusted Startup and Verification Scheme
abstract: The rapid development of blockchain technology has aroused people's attention to its security issues. The immutability and non repudiation of the blockchain ensure the security of upper level data and networks, but the existing mechanisms of the blockchain have always been difficult to guarantee its underlying Security. This paper proposes a method for verifying the trusted launch of a blockchain, which is used for trusted verification before the launch of a blockchain network. This method mainly uses a solution that combines trusted computing and blockchain networks in cloud scenarios to solve the integrity and security issues at the start of the blockchain to prevent potential problems. The architecture of this article is composed of a blockchain network, SGX Application and cloud database. We build a trust chain based on key services and files when the blockchain is started, and use integrity verification to transfer trust. Hashing is performed with the support of SGX to ensure the security of the verification process. Under the condition that the performance at the time of loss is about 50% to 62% the underlying security is fully guaranteed.

title: Bottom up: A SGX based Blockchain Trusted Startup and Verification Scheme

title: A Survey on the Application of SGX in Blockchain Area

title: P2A: Privacy Preserving Anonymous Authentication Based on Blockchain and SGX

title: SDABS: A Secure Cloud Data Auditing Scheme Based on Blockchain and SGX

title: Accountable Data Sharing Scheme Based on Blockchain and SGX
abstract: Nowadays, data has been more intensive and collaborative than in the past. In this paper, we propose a new accountable data sharing scheme based on blockchain and SGX, in which data subscription undeniable. By utilizing blockchain, the records of users data sharing acts are tamper resistant, and our scheme no longer needs a trusted third party. SGX ensures the confidentiality of sharing data.