With the emergence of network function virtualization (NFV), and software-defined networking (SDN), the realization and implementation of service function chains (SFCs) have become much easier. An SFC is an ordered set of interconnected virtual network functions (VNFs). NFV allows for decoupling the network functions from proprietary hardware realizing a software-based implementation of VNFs on commodity hardware and SDN decouples the network control from its forwarding logic allowing for a more flexible and programmable traffic routing among the VNFs. The SFC embedding problem (i.e. placement of SFCs on a shared substrate and establishing the corresponding traffic routes between the VNFs), has been extensively studied in the literature. In this paper, we extend a previous work on trust-aware service chain embedding with generalizing the role of trust by incorporating the trustworthiness of the service network links and substrate network paths into the SFC embedding decision process. We first introduce and formulate the path-based trust-aware service chain embedding problem as a mixed integer-linear program (MILP), and then provide an approximate model-based on selecting k-shortest candidate substrate paths for hosting each virtual link, to reduce the complexity of the model. We validate the performance of our methods through simulations and conduct a discussion on evaluating the methods and some operation trade-offs.

中文翻译：

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信任感知服务功能链嵌入：一种基于路径的方法

随着网络功能虚拟化（NFV）和软件定义网络（SDN）的出现，服务功能链（SFC）的实现和实现变得更加容易。SFC 是一组有序的互连虚拟网络功能 (VNF)。NFV 允许将网络功能与专有硬件分离，从而在商品硬件上实现基于软件的 VNF 实现，SDN 将网络控制与其转发逻辑分离，从而在 VNF 之间实现更灵活和可编程的流量路由。SFC 嵌入问题（即在共享基板上放置 SFC 并在 VNF 之间建立相应的交通路线）已在文献中进行了广泛研究。在本文中，我们扩展了先前关于信任感知服务链嵌入的工作，通过将服务网络链接和底层网络路径的可信度纳入 SFC 嵌入决策过程来概括信任的作用。我们首先将基于路径的信任感知服务链嵌入问题引入并表述为混合整数线性规划（MILP），然后提供基于选择 k 最短候选基板路径来托管每个虚拟链接的近似模型，以降低模型的复杂度。我们通过模拟验证我们方法的性能，并就评估方法和一些操作权衡进行讨论。我们首先将基于路径的信任感知服务链嵌入问题引入并表述为混合整数线性规划（MILP），然后提供基于选择 k 最短候选基板路径来托管每个虚拟链接的近似模型，以降低模型的复杂度。我们通过模拟验证我们方法的性能，并就评估方法和一些操作权衡进行讨论。我们首先将基于路径的信任感知服务链嵌入问题引入并表述为混合整数线性规划（MILP），然后提供基于选择 k 最短候选基板路径来托管每个虚拟链接的近似模型，以降低模型的复杂度。我们通过模拟验证我们方法的性能，并就评估方法和一些操作权衡进行讨论。