Smart contracts enable users to execute payments depending on complex program logic. Ethereum is the most notable example of a blockchain that supports smart contracts leveraged for countless applications including games, auctions and financial products. Unfortunately, the traditional method of running contract code on-chain is very expensive, for instance, on the Ethereum platform, fees have dramatically increased, rendering the system unsuitable for complex applications. A prominent solution to address this problem is to execute code off-chain and only use the blockchain as a trust anchor. While there has been significant progress in developing off-chain systems over the last years, current off-chain solutions suffer from various drawbacks including costly blockchain interactions, lack of data privacy, huge capital costs from locked collateral, or supporting only a restricted set of applications. In this paper, we present POSE -- a practical off-chain protocol for smart contracts that addresses the aforementioned shortcomings of existing solutions. POSE leverages a pool of Trusted Execution Environments (TEEs) to execute the computation efficiently and to swiftly recover from accidental or malicious failures. We show that POSE provides strong security guarantees even if a large subset of parties is corrupted. We evaluate our proof-of-concept implementation with respect to its efficiency and effectiveness.
翻译:智能合同使用户能够根据复杂的程序逻辑执行付款。 Eceenum 是支持智能合同的链条中最显著的例子,它支持智能合同,为游戏、拍卖和金融产品等无数应用提供杠杆效应。 不幸的是,传统的链条合同编码操作方法非常昂贵,例如Etherem平台上的费用急剧增加,使系统不适于复杂的应用。 解决这一问题的一个突出解决办法是执行离链编码,只将链条作为信托锚。 虽然过去几年在发展离链系统方面取得了重大进展,但目前的离链解决方案受到各种缺陷的影响,包括昂贵的链条互动、缺乏数据隐私、锁定抵押品的巨额资本成本,或仅支持一套限制性的应用。在本文件中,我们介绍POSE -- -- 解决上述现有解决方案缺陷的智能合同的一个实用的离链协议。 POSE利用信任执行环境(TEs)来高效地进行计算,并从意外或恶意的失败中迅速恢复。我们显示,即使一大批当事方违约,OSEE提供强有力的安全保障。我们评估其有效性。