Early reports on the acquisition picked up this definition of Xsigo’s I/O virtualization appliance and ran with it, lumping the Xsigo purchase in with VMware’s blockbuster acquisition last week of networking virtualization player Nicira.
Then came the social media outrage. The term “SDN-washing” was thrown around.
Quoth Joe Onisick (@jonisick) on Twitter:
“Xsigo is to SDN what McDonald’s is to fine dining.”
A little while later, Nicholas Weaver (@lynxbat) chimed in with this gem:
“Every time a tech reporter compares Xsigo to Nicira, a puppy dies.”
Xsigo officials responded with a link to a whitepaper called Xsigo Fabric Accelerator: Virtualized Infrastructure as evidence of their software-definedness. To wit:
Xsigo Fabric Accelerator defines connectivity entirely in software using a supremely elegant resource – the Private Virtual Interconnect.
The Private Virtual Interconnect is the ultimate software defined network. It is the connectivity equivalent of the virtual machine. It lets you connect any virtual machine to any other resource, including virtual machines, virtual appliances, bare-metal servers, networks and storage, anywhere in the data center. Connect in seconds without inflexible network configuration, and gain the flexibility and agility you need to take control of your cloud.
But the IT community ain’t having it.
“My first reaction is that is a stretch,” said Greg Schulz, founder of Server and Storage I/O Group. By this standard, “you could argue that the software inside a [Cisco] Catalyst makes it software-defined.”
The Open Networking Foundation defines SDN as networking technology which meets the following criteria:
- Separation of the control plane from the data plane
- A centralized controller and view of the network
- Programmability of the network by external applications
Those who object to Xsigo being called software-defined networking cite the fact that Xsigo’s Fabric Accelerator runs exclusively within Xsigo’s Fabric Director as a closed, proprietary hardware-based appliance. While Xsigo can be plugged into a network, it’s a kind of “black box” where I/O virtualization magic happens, rather than an open system that can be plugged in to a central third-party controller.
By contrast, most players in the software-defined networking game, including Nicira, use the OpenFlow protocol in one way or another to achieve network visibility, control and programmability across multiple switches.
Do you think Xsigo should be considered SDN? Share your comments below.