Enforcing trustworthy cloud SLA with witnesses: A game theory–based model using smart contracts

Abstract

Summary There lacks trust between the cloud customer and provider to enforce traditional cloud SLA (Service Level Agreement) where the blockchain technique seems a promising solution. However, current explorations still face challenges to prove that the off‐chain SLO (Service Level Objective) violations really happen before recorded into the on‐chain transactions. In this paper, a witness model is proposed implemented with smart contracts to solve this trust issue. The introduced role, “Witness”, gains rewards as an incentive for performing the SLO violation report, and the payoff function is carefully designed in a way that the witness has to tell the truth, for maximizing the rewards. This fact that the witness has to be honest is analyzed and proved using the Nash Equilibrium principle of game theory. For ensuring the chosen witnesses are random and independent, an unbiased selection algorithm is proposed to avoid possible collusions. An auditing mechanism is also introduced to detect potential malicious witnesses. Specifically, we define three types of malicious behaviors and propose quantitative indicators to audit and detect these behaviors. Moreover, experimental studies based on Ethereum blockchain demonstrate the proposed model is feasible, and indicate that the performance, ie, transaction fee, of each interface follows the design expectations.

Smart Contracts for Service-Level Agreements in Edge-to-Cloud Computing

“…However, in such schemata, all participants are obliged to trust a centralised third-party broker. Since trusting a third-party SLA management system can be difficult in reality, a blockchain-based SLA management system can aid to overcome that problem [36,37], where the blockchain offers complete transparency and SLAs are precisely declared in the SC. In addition, blockchain integration into SLA management systems can lead towards a automated, simplified and less expensive sharing of infrastructures using SLA [13] and compensation between providers and consumers in case of SLA violation [25].…”

Digital Enforceable Contracts (DEC): Making Smart Contracts Smarter

“…Finally, for each type of enforcement we set up a simulation to test whether the proposed solution functions as expected. 4 In the following paragraphs we show how our proposed architecture and the reasoning mechanism can be used for ex-ante enforcement as well as for ex-post enforcement.…”

“…Enforcement can also be achieved by means of dedicated social infrastructures. For instance, [4] proposes a model of incentives to enable enforcement for off-chain activities. On similar lines, in production settings, consider e.g.…”

“…More concretely, the models we used were written in eFLINT[6], a language for specifying policies based on normative frames. Note however that any other choices would have been equally good in functional terms 4. The code used for the proof of concept can be found on https://gitlab.com/evelynliu324/ digital-enforceable-contract.L.-C. Liu et al / Digital Enforceable Contracts (DEC): Making Smart Contracts Smarter…”

An Automated Customization and Performance Profiling Framework for Permissioned Blockchains in a Virtualized Environment

“…The blockchain technologies have demonstrated their great potential to provide trustworthy and security services in various industrial scenarios such as Internet of Things (IoT) [1], intellectual property management [2], Service Level Agreement(SLA) enforcement [3] [4], and stock exchange trading [5]. It records transactions among participants as identical copies through a decentralized ledger and generates new blocks based on a specific consensus algorithm.…”