Phala Network: A Secure Decentralized Cloud Computing Network Based on Polkadot
Phala Network: A Secure Decentralized Cloud Computing Network Based on Polkadot
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Phala Network：基于 Polkadot 的安全去中心化云计算网络
DOI：
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发表时间：
2022
期刊：
影响因子：
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通讯作者：
Jun Jiang
中科院分区：
文献类型：
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作者：
Hang Yin;Shunfan Zhou;Jun Jiang
如今，无权限区块链的安全性通常通过共识算法上的状态复制来保证。虽然这种方法在区块链上运行良好，但这也意味着区块链上的所有内容都是公开的，这带来了一个问题：区块链无法处理机密信息。缺乏保密性极大地限制了区块链在处理敏感业务和用户数据方面的使用。例如，股票交易员通常不想透露他们的头寸或订单历史。更重要的是，以太坊上所有与隐私相关的DApp都不符合《通用数据保护条例》，因此将在欧盟被禁止。已经提出了几种方法来解决隐私问题。Monero和Zcash通过环签名[13]和zk-SNARK [11]技术实现了私有交易，但他们的方法只能为加密货币提供隐私，很难扩展到通用智能合约。MPC（多方计算）理论上可以运行任意程序，而不会向参与者透露中间状态，代价是10倍的性能开销[9]，这使得它在真实的世界用例中不切实际。一种新的方法是利用特殊的硬件，即，可信执行环境（TEE）[8]。TEE是某些处理器中的一个特殊区域，提供更高级别的安全性，包括隔离执行、代码集成和状态机密性。朴素TEE作为一种计算平台存在着一些不足，如缺乏可靠的时间源和可用性保证。Ekiden [9]通过引入TEE-区块链混合架构解决了这些问题，并实现了高性能的机密智能合约平台。然而，Ekiden中的合约是孤立的，这意味着合约无法相互操作，更不用说外部区块链了。互操作性是现代智能合约的基石。例如，世界上最大的智能合约平台以太坊的前10个合约中有8个依赖于函数调用或资金转移到至少一个其他合约。如果没有互操作性，合约就无法从其他智能合约读取信息或调用函数。更重要的是，使用自定义令牌，
Nowadays the security of the permissionless blockchain is typically guaranteed by state replication over consensus algorithms. Though this approach works well for blockchain, it also means that everything on the blockchain is public, which brings a problem: confidential information cannot be handled by the blockchain. The lack of confidentiality greatly limits the usage of blockchain in processing sensitive business and user data. For example, stock traders usually do not want to reveal their positions or order history. What’s more, all of the privacy-related DApps on the Ethereum cannot comply with the General Data Protection Regulation and thus will be prevented in European Union. Several methodologies have been proposed to address the privacy problem. Monero and Zcash implemented private transaction by ring signature [13] and zk-SNARK [11] technology, but their methods can only provide privacy for cryptocurrencies and are hard to be extended to general-purpose smart contracts. MPC (Multi-Party Computing) can theoretically run arbitrary programs without revealing intermediate states to the participants, with the expense of a performance overhead of 10 times [9], which makes it impractical for real world use cases. A new approach is to utilize special hardware, i.e., Trusted Execution Environment (TEE) [8]. TEE is a special area in some processors that provides a higher level of security including isolated execution, code integration, and state confidentiality. Naive TEE as a computing platform has several shortages, such as the lack of a reliable time source and availability guarantee. Ekiden [9] fixed these problems by introducing a TEE-blockchain hybrid architecture and implemented a high performance confidential smart contract platform. However, contracts in Ekiden are isolated, which means the contracts cannot interoperate with each other, let alone external blockchains. Interoperability is a keystone of modern smart contracts. For example, 8 of the top 10 contracts in Ethereum, the largest smart contract platform in the world, rely on functions invocations or money transferring to at least one other contract. Without interoperability, contracts cannot read information or call functions from other smart contracts. What’s more, the use of self-defined tokens, one
DOI：
10.1109/eurosp.2019.00023
发表时间：
2018-04
期刊：
2019 IEEE European Symposium on Security and Privacy (EuroS&P)
影响因子：
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作者：
Raymond Cheng;Fan Zhang;Jernej Kos;Warren He;Nicholas Hynes;Noah M. Johnson;A. Juels;Andrew K. Miller-Andre
通讯作者：
Raymond Cheng;Fan Zhang;Jernej Kos;Warren He;Nicholas Hynes;Noah M. Johnson;A. Juels;Andrew K. Miller-Andre