Software-Defined Networking with Windows Server 2016

Improved network automation was one of Microsoft’s key goals during the development of the latest version of its flagship server operating system. Windows Server 2016 achieves that with an enhanced networking stack in which software-defined networking (SDN) functionality is transferred directly from its Azure cloud platform.

Traditional hardware-centric network infrastructures are rigid and complex, making them increasingly ill-suited for today’s virtualized, cloud-based and mobility-enhanced environments. SDN creates a layer of software that works with your existing hardware to eliminate this rigidity.

With SDN, the software layer assumes control of the network by virtualizing functions such as switching, routing, load balancing, firewalls and edge services. This gives you the ability to dynamically manage applications and workloads — without the need to re-engineer the base physical network.

Although Microsoft included SDN features in Windows Server 2012, the company dramatically polished and refined its SDN capabilities over the past few years, largely out of necessity. Microsoft’s Azure public cloud delivers the company’s software products from more than 100 data centers around the world. Storage and compute usage is doubling each month, and approximately 1,000 new Azure users are added every day.

To accommodate this growth, Microsoft built an SDN stack from scratch, writing all its own code and developing new APIs and controllers. These features are included with Windows Server 2016, giving you the same SDN capabilities that power Azure in the cloud:

• Network Controller is a highly available and scalable server role. It is ported from the Azure stack to provide a centralized, programmable point of automation. Using Network Controller, you can automate the configuration of network infrastructure instead of performing manual configuration of network devices and services.
• Hyper-V Network Virtualization helps you abstract applications and workloads using virtual networks that provide multi-tenant isolation on a shared physical network fabric. For investment protection, virtual networks can be set up on existing networking gear.
• The Hyper-V Virtual Switch is a software-based layer-2 Ethernet network switch that can connect virtual machines to both virtual networks and the physical network. In addition, Hyper-V Virtual Switch provides policy enforcement for security, isolation and service levels.
• Network Functions Virtualization allows you to virtualize functions that are typically performed by hardware appliances such as load balancers and firewalls. Moving these services onto software that can run on any white box server results in better resource management, reduced expenses and faster provisioning.

All of these features bring a great deal of flexibility to traditional network designs, in which tiers of switches and routers implement diverse protocols to connect devices using proprietary interfaces. Any change to the network requires multiple updates using device-level management tools. That is becoming a huge problem in highly virtualized environments in which IT may have to configure thousands of virtual machines. Significant changes can take days or weeks, and makes it difficult to apply a consistent set of access, security and other policies.

With Windows Server 2016, Microsoft delivers on the SDN vision in which software accelerates the pace of innovation for networks as it has in the computing and storage domains. Windows Server 2016’s SDN features deliver the intelligence to allocate resources dynamically, the scale to support enormous data centers and the virtualization needed to support dynamic, highly automated and secure cloud environments.

Written and composed by our Senior Microsoft Systems Engineer, Alex Levin