Next generation of Internet of Things (IoT) services imposes stringent requirements to the future networks that current ones cannot fulfill. 5G is a technology born to give response to those requirements. However, the deployment of 5G is also accompanied by profound architectural changes in the network, including the introduction of technologies like multi-access edge computing (MEC), software defined networking (SDN), and network function virtualization (NFV). In particular, NFV poses diverse challenges like virtual network function (VNF) placement and chaining, also called VNF-mapping. In this paper, we present an algorithm that solves VNF-placement and chaining in a metro WDM optical network equipped with MEC resources. Therefore, it solves the VNF-mapping in conjunction with the virtual topology design of the underlying optical backhaul network. Moreover, a version of the method providing protection against node failures is also presented. A simulation study is presented to show the importance of designing the three problems jointly, in contrast to other proposals of the literature that do not take the design of the underlying network into consideration when solving that problem. Furthermore, this paper also shows the advantages of using collaboration between MEC nodes to solve the VNF-mapping problem and the advantage of using shared protection schemes. The new algorithm outperforms other proposals in terms of both service blocking ratio, and number of active CPUs (thus reducing energy consumption). Finally, the impact of deploying different physical topologies for the optical backhaul network is also presented.

中文翻译：

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用于整体 VNF 映射和虚拟拓扑设计的遗传算法

下一代物联网 (IoT) 服务对未来网络提出了当前无法满足的严格要求。5G 是一种为满足这些需求而生的技术。然而，5G的部署也伴随着网络架构的深刻变革，包括多接入边缘计算（MEC）、软件定义网络（SDN）、网络功能虚拟化（NFV）等技术的引入。特别是，NFV 带来了各种挑战，例如虚拟网络功能 (VNF) 放置和链接，也称为 VNF 映射。在本文中，我们提出了一种在配备 MEC 资源的城域 WDM 光网络中解决 VNF 放置和链接的算法。所以，它结合底层光回程网络的虚拟拓扑设计解决了VNF映射。此外，还介绍了提供节点故障保护的方法版本。提出了一项模拟研究，以表明联合设计这三个问题的重要性，这与在解决该问题时未考虑底层网络设计的其他文献建议形成对比。此外，本文还展示了使用 MEC 节点之间的协作来解决 VNF 映射问题的优势以及使用共享保护方案的优势。新算法在服务阻塞率和活动 CPU 数量（从而降低能耗）方面均优于其他提议。最后，