Why Interoperability Matters in Software-Defined Networking, and How Microsoft Fits In

Software-defined networking (SDN) provides some important capabilities to help you get the best performance from applications running within your network environment. Essentially, both physical and virtual network devices, as well as the applications that leverage them (e.g., SQL Server, SharePoint), can work in concert and communicate with one another to deliver a truly dynamic, scalable network. This seamless communication requires interoperability between the various networking vendor products that are implemented on your network. Several standards have arisen around these north- and southbound interfaces, and Microsoft is an active participant in these standards.

Physical network devices and applications come from different vendors. Most customer networks are composed of a variety of these vendor products. Therefore, truly automated SDN that seamlessly lets workloads communicate with one another, regardless of where they are hosted, requires communication throughout all the physical and virtual pieces of the network. To accomplish this, SDN-solution vendors such as Microsoft must provide interoperability between their technologies and north- and southbound interfaces.

For example, Windows Server Hyper-V provides an extensible virtual switch architecture—the v-switch—that lets third-party vendors add functionality. Cisco has implemented the Nexus 1000 switching technology in the Hyper-V switch to provide additional features, and a standard Cisco management interface, to Hyper-V virtual networking. In addition, NEC provides a Windows Server Hyper-V Switch Extension that provides OpenFlow-compatible filtering, capturing, and forwarding of traffic through the virtual switch. And vendors such as 5Nine and InMon provide virtual machine (VM) isolation and traffic routing as value-added extensions to the Hyper-V virtual switch.

Maybe you have a server workload, such as SharePoint, running in a private cloud, which requires additional web front ends to deal with intermittent demand increases. You might want your virtualization infrastructure to be flexible enough to deploy that temporary workload in a public cloud environment such as Windows Azure. Or you might have TOR switches that you need to manage from your Hyper-V management tools. To accomplish all these tasks, your SDN solution must be able to communicate across vendor products—allowing for automation of physical and virtual networking configuration as needs change. This is where interoperability between your SDN solution and the various networking products that run in your infrastructure is vital and where standards take center stage.

The challenge, of course, is that each vendor might adhere to different standards with respect to interoperability and communication between devices. There’s good news if you use Microsoft Hyper-V:Microsoft is involved in numerous standards bodies for SDN technologies, including Open Daylight and Open Networking (see Democratizing SDN, Rajeev Nagar | OpenDaylight Summit 2014) as well DMTF and IETF. In addition, Microsoft has contributed the open source Open Management Infrastructure (OMI) stack, which allows multiple, non-Windows platforms to implement a DMTF Common Information Model (CIM) stack. This is similar to Windows WMI, which eases cross-platform manageability and automation. What does OMI provide? For vendors that implement OMI stacks on their network devices, such as Cisco with their Nexus 3000 and Arista with their TOR switches, you can use a single set of management tools (e.g., PowerShell, other CIM-aware tools) to manage across Hyper-V, Windows Server, and your physical networking devices from other vendors. This unified cross-platform management interface can be truly compelling when you think about the automation scenarios that it enables.

So how does all this interoperability help the customer implementing a virtual data center? Well, in all my years in IT, I’ve never come across an enterprise that has a single vendor across their entire infrastructure stack. Cisco switches, Juniper routers, Windows Servers—you name it and most enterprises run it. Likewise, most enterprises I come across struggle with multiple management tools that are siloed to each vendor solution. If they are lucky, they might be able to rely on some least-common-denominator management standard such as SNMP to glean information from across these infrastructure pieces and vendors.

What SDN, and interoperability standards between vendors, promise and demand are the tools to enable users to manage their virtual datacenter and networks with a unified toolset, policies, and orchestration. In the Windows world, I can use PowerShell to manage almost every aspect of Hyper-V and its component configurations, as well as Windows Server and its features. Now imagine a scenario where I use a PowerShell script to provision a set of VMs running SharePoint in Hyper-V, configure their virtual NIC on a Cisco Nexus 1000V virtual switch extension to Hyper-V’s virtual switch, and then configure an Arista TOR switch to set access controls for the new VMs. All this is possible through SDN and standards-based management technologies. I would argue that for SDN to be successful and for customers to benefit from it in truly meaningful ways, this interoperability between SDN solutions and your network components is a must—one that promises to take virtual networking to the next level. To learn more about SDN solutions, visit http://www.microsoft.com/en-us/server-cloud/solutions/software-defined-networking.aspx?code=witp#fbid=LaAUjM8aHUEhttp://www.microsoft.com/en-us/server-cloud/solutions/software-defined-networking.aspx.