Current network virtualization allows tenants to have their own virtual networks. However, new demands to "program" virtual networks at a finer granularity have arisen as tenants want the ability to provision and control switches and links in their virtual networks. This study proposes a new concept called the p-NIaaS model. The p-NIaaS model enables tenants to program their own packet processing logic and monitor network status from any virtual network infrastructure, which is not possible with current network virtualization. This article presents the Libera network hypervisor that implements the p-NIaaS model. Libera overcomes the shortcomings of existing network hypervisors such as scalability, VM migration support, and flexibility. The evaluation shows that the Libera hypervisor is highly scalable and effectively supports VM migration. We also present the overheads of Libera. Libera incurs up to 11 percent overhead in comparison with a non-virtualized network, which we believe is promising in the first prototype of the p-NIaaS model.

中文翻译：

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用于可编程网络虚拟化的 Libera

当前的网络虚拟化允许租户拥有自己的虚拟网络。然而，随着租户希望能够在其虚拟网络中配置和控制交换机和链路，出现了以更细粒度“编程”虚拟网络的新需求。这项研究提出了一个新概念，称为 p-NIaaS 模型。p-NIaaS 模型使租户能够对自己的数据包处理逻辑进行编程，并从任何虚拟网络基础设施监控网络状态，这在当前的网络虚拟化中是不可能的。本文介绍了实现 p-NIaaS 模型的 Libera 网络管理程序。Libera 克服了现有网络管理程序的缺点，例如可扩展性、VM 迁移支持和灵活性。评估表明，Libera hypervisor 具有高度可扩展性，并有效支持 VM 迁移。我们还介绍了 Libera 的管理费用。与非虚拟化网络相比，Libera 产生高达 11% 的开销，我们认为这在 p-NIaaS 模型的第一个原型中很有前景。