Network Function Virtualization (NFV) brings flexible provisioning and great convenience for enterprises outsource their network functions to the Data Center Networks (DCNs). Network service in NFV is deployed as a Service Function Chain (SFC), which includes an ordered set of Virtual Network Functions (VNFs). However, in one SFC, the SFC delay increases linearly as the length of SFC increases. SFC parallelism can achieve high performance of SFC. In this article, we focus on the parallelized SFC placement problem in DCN considering availability guarantee and resource optimization. Firstly, we define the parallelized SFC and propose a multi-flow backup model. The parallelized SFC consists of multiple parallelized sub-SFCs. We split large data flow into multiple small sub-flows, each of them can be transmitted in one sub-SFC. The backup model provides backup sub-SFCs for working sub-SFCs to improve availability. Finally, we design three placement strategies and a Hybrid Placement Algorithm (HPA) aimed at mapping SFCs to DCN. Evaluation results show that our proposed solutions outperform the related work. We can reduce SFC delay (30%) and optimize link consumption (reduce 40%) while guaranteeing availability (99.999%).

中文翻译：

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数据中心网络中并行SFC的可用性和流量感知布局

网络功能虚拟化（NFV）为企业提供了灵活的配置和极大的便利，可将网络功能外包给数据中心网络（DCN）。NFV中的网络服务被部署为服务功能链（SFC），其中包括一组有序的虚拟网络功能（VNF）。但是，在一个SFC中，SFC延迟随着SFC长度的增加而线性增加。SFC并行性可以实现SFC的高性能。在本文中，我们着重考虑可用性保证和资源优化的DCN中并行化SFC放置问题。首先，我们定义并行化的SFC，并提出一种多流备份模型。并行SFC由多个并行子SFC组成。我们将大数据流划分为多个小子流，每个子流都可以在一个子SFC中传输。备份模型为工作的子SFC提供了备份子SFC，以提高可用性。最后，我们设计了三种放置策略和一种旨在将SFC映射到DCN的混合放置算法（HPA）。评估结果表明，我们提出的解决方案优于相关工作。我们可以减少SFC延迟（30％），优化链路消耗（减少40％），同时保证可用性（99.999％）。