Analysis of a trust model for SLA negotiation and enforcement in cloud markets

Abstract

Online Reputation Systems help mitigate the information asymmetry between clients and providers in Cloud Computing Markets. However, those systems raise two main drawbacks: the disagreement for assuming the cost of ownership of such services and their vulnerability to reputation attacks from dishonest parties that want to increase their reputation. This article faces both problems by describing a decentralised (peer-topeer) trust model that does not require the intervention of a central entity to manage it. This model includes mechanisms to allow participants to avoid dishonest behaviour from other peers: each client statistically analyses the external reports about providers and updates the trustworthiness of the peers. The trustworthiness values will be used to negotiate prices in later transactions. The trust model is then incorporated in the Service-Level Agreement negotiation and enforcement processes, prioritising trusted clients over non-trusted clients to minimise the consequences of low Quality of Service in relation to the trust of the provider, and incentivise accurate trust reports from the clients. Finally, this article evaluates and discusses the validity of the trust model under different attacks from dishonest clients and providers.

Logistics and cloud computing service providers’ cooperation: a resilience perspective

“…Macías and Guitart (2016) posit that CC service providers can violate Service Level Agreement (SLA) with their clients through poor administrative control or even outright dishonest behaviour. A study by Alali and Yeh (2012) furthermore indicates that unclear or limited legal standards regarding compensation and responsibility coupled with a lack of regulatory guidance that support its users complicate trust issues.…”

“…Additionally, the lack of security guarantees in the service level agreement (SLA) has seriously questioned CC service providers' capability to keep customers' data secured (Morsy, Grundy, and Muller 2010;Macías and Guitart 2016).…”

“…For example, the transport system that relies on CC services expects the elimination or reduction of service disruption, degradations and other vulnerabilities resulting from CC service failures. However, such needed guarantee is not forthcoming due to a lack of security guarantees in the service level agreement (SLA) by CC service providers (Morsy, Grundy, and Muller 2010;Macías and Guitart 2016) coupled with inherent difficulties of establishing trust between parties that are autonomous entities and geographically separated (Bose, Luo, and Liu 2013).…”

“…Furthermore, CC services suffer from unclear or limited legal standards regarding compensation and responsibility to service consumers (Macías and Guitart 2016;Srivastava 2004). This is in addition to a lack of regulatory guidance to support CC users further substantially erodes trust in CC adoption (Alali and Yeh 2012).…”

Mixed integer linear programming for quality of service optimization in Clouds

“…• Decentralized resource allocation approaches for QoS based on negotiation and/or in game theory [8,9],…”