We consider several Software as a Service (SaaS) providers that offer services using the Cloud resources provided by an Infrastructure as a Service (IaaS) provider which adopts a pay-per-use scheme similar to the Amazon EC2 service, comprising flat, on demand, and spot virtual machine instances. For this scenario, we study the virtual machine provisioning and spot pricing strategies. We consider a two-stage provisioning scheme. In the first stage, the SaaS providers determine the optimal number of required flat and on demand instances. Then, in the second stage, the IaaS provider sells its unused capacity as spot instances for which the SaaS providers compete by submitting a bid. We study two different IaaS provider pricing strategies: the first assumes the IaaS provider sets a unique price; in the second, instead, the IaaS provider can set different prices for different customers. We model the resulting problem as a Stackelberg game. For each pricing scheme, we show the existence of the game equilibrium and provide the solution algorithms. Through numerical evaluation we compare the provisioning and spot price under the two different pricing strategies as function of the system parameters.

中文翻译：

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云系统中的博弈论资源定价和供应策略

我们考虑了几个软件即服务 (SaaS) 提供商，这些提供商使用基础设施即服务 (IaaS) 提供商提供的云资源提供服务，该提供商采用类似于 Amazon EC2 服务的按使用付费方案，包括平面、按需，并发现虚拟机实例。对于这种情况，我们研究了虚拟机配置和现货定价策略。我们考虑一个两阶段的配置方案。在第一阶段，SaaS 提供商确定所需的平面和按需实例的最佳数量。然后，在第二阶段，IaaS 提供商将其未使用的容量作为 Spot 实例出售，SaaS 提供商通过提交投标进行竞争。我们研究了两种不同的 IaaS 供应商定价策略：第一种假设 IaaS 供应商设定唯一的价格；在第二个，相反，IaaS 提供商可以为不同的客户设置不同的价格。我们将由此产生的问题建模为 Stackelberg 游戏。对于每个定价方案，我们展示了博弈均衡的存在性并提供了求解算法。通过数值评估，我们将两种不同定价策略下的供应价格和现货价格作为系统参数的函数进行比较。