The Mobile Edge-Cloud (MEC) network has emerged as a promising networking paradigm to address the conflict between increasing computing-intensive applications and resource-constrained mobile Internet-of-Thing (IoT) devices with portable size and storage. In MEC environments, Virtualized Network Functions (VNFs) are deployed for provisioning network services to users to reduce the service cost on top of dedicated hardware infrastructures. However, VNFs may suffer from failures and malfunctions while network service providers have to guarantee continuously reliable services to their consumers to meet the ever-growing service demands of users, thereby securing their revenues for the service. In this article, we focus on reliable VNF service provisioning in MECs, by placing primary and backup VNF instances to cloudlets in an MEC network to meet the service reliability requirements of users. We first formulate a novel VNF service reliability problem with the aim to maximize the revenue collected by admitting as many as user requests while meeting their different reliability requirements, assuming that requests arrive into the system one by one without the knowledge of future arrivals, and the admission or rejection decision must be made immediately. We then develop two efficient online algorithms for the problem under two different backup schemes: the on-site (local) and off-site (remote) schemes, by adopting the primal-dual updating technique. Both algorithms achieve provable competitive ratios with bounded moderate resource capacity violations. We finally evaluate the proposed algorithms through experimental simulations. Experimental results demonstrate that the proposed algorithms are promising, compared with existing baseline algorithms.

中文翻译：

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移动边缘云网络中的可靠性感知网络服务提供

移动边缘云 (MEC) 网络已成为解决日益增长的计算密集型应用程序与具有便携尺寸和存储的资源受限的移动物联网 (IoT) 设备之间冲突的有前途的网络范例。在 MEC 环境中，部署虚拟化网络功能 (VNF) 以向用户提供网络服务，以降低专用硬件基础设施之上的服务成本。然而，VNF 可能会出现故障和故障，而网络服务提供商必须保证为消费者提供持续可靠的服务，以满足用户不断增长的服务需求，从而确保他们的服务收入。在本文中，我们重点介绍 MEC 中可靠的 VNF 服务供应，通过将主备VNF实例放置到MEC网络中的cloudlets，满足用户的业务可靠性需求。我们首先制定了一个新的 VNF 服务可靠性问题，目的是通过接纳尽可能多的用户请求同时满足他们不同的可靠性要求来最大化收集的收入，假设请求在不知道未来到达的情况下逐个到达系统，并且必须立即做出录取或拒绝决定。然后，我们通过采用原始-双重更新技术，在两种不同的备份方案下为该问题开发了两种有效的在线算法：现场（本地）和异地（远程）方案。两种算法都实现了可证明的竞争比率，并且具有有限的中等资源容量违规。我们最终通过实验模拟评估了所提出的算法。实验结果表明，与现有的基线算法相比，所提出的算法是有前途的。