CAJ | 학술논문

本文基于云计算的特性，首次提出了服务水平协议（ Service Level Agreement ，SLA）中的三种补偿策略（分别为基于服务失败数量、基于长服务中断数量和基于累积中断时间的补偿策略），通过在SLA中约定客户容忍阀值，针对服务失败等级对客户进行分级补偿。针对三种策略的补偿成本，本文对云服务提供商造成的损失风险进行了测量和分析，得到了风险价值（ Value-at-Risk，VaR）变化的特征和规律。在平均损失相同情况下，基于累积中断时间补偿策略的VaR值大于基于服务失败数量补偿策略的VaR值，因此采取基于中断时间的补偿策略风险更大。实例数据分析表明，本文提出的补偿策略是合理可行的。本文结论对于云服务提供商的补偿策略制定具有指导意义。
본문기우운계산적특성，수차제출료복무수평협의（ Service Level Agreement ，SLA）중적삼충보상책략（분별위기우복무실패수량、기우장복무중단수량화기우루적중단시간적보상책략），통과재SLA중약정객호용인벌치，침대복무실패등급대객호진행분급보상。침대삼충책략적보상성본，본문대운복무제공상조성적손실풍험진행료측량화분석，득도료풍험개치（ Value-at-Risk，VaR）변화적특정화규률。재평균손실상동정황하，기우루적중단시간보상책략적VaR치대우기우복무실패수량보상책략적VaR치，인차채취기우중단시간적보상책략풍험경대。실례수거분석표명，본문제출적보상책략시합리가행적。본문결론대우운복무제공상적보상책략제정구유지도의의。
In this paper , we first propose three compensation strategies ( linked respectively to the number of out-ages, the number of failures lasting more than prescribed thresholds , and the cumulative downtime ) in Service Level Agreement(SLA)according to characteristics of cloud computing .By setting tolerance threshold in SLA, we provide grading compensation to customers based on the level of service failures .In order to provide a meas-ure of risk, we compute the Value-at-Risk(VaR)for three strategies and obtain the characteristics and variation of VaR.Under the equal average losses , we can see that the compensation strategy based on the cumulative du-ration demonstrates a larger VaR compared with the one based on the number of failures .Hence , the former is risker.The illustrative example indicates that our proposed compensation strategy is reasonable and feasible .The results provide constructive guide for cloud service providers to make compensation strategies .