SDN Technology Considerations – EMA

An EMA Researcher's opinion on Commodity switches, Disaggregation vs. Controllers and Overlay concerns.

SDN Technology Considerations – An Expert’s Point of View (4 min)

  • Shamus McGillicuddy, Senior Analyst, EMA Research

Do Commodity Switches perform as well as Proprietary Switches?

  • Every OEM switch manufacturer uses off-the-shelf network silicon today. The same Broadcom chips you find in a commodity switch can be found in a Cisco switch. While other companies do develop their own ASICs for some use cases, but others rely on off-the-shelf silicon everywhere. You won’t see much difference in network performance. Only in feature sets.
  • Companies that specialize in software for commodity hardware have demonstrated the ability to innovate in software in ways that make them competitive with traditional switch makers. The real difference with commodity hardware is cultural and technical proficiency. Some organizations are more accustomed to buying vertically integrated products that are provisioned and managed in a certain way.

When it comes to Disaggregation and Controllers, what do users care about?

  • Early adopters of SDN consider the disaggregation of the control plane and the data plane to be the least important characteristic of the SDN solutions they choose. They don’t care if some or all of the control plane is separated from the data plane devices. Instead, they are focused on having a controller that can serve as the central point of management, programmability and visibility into the network.

What about Overlays, what are the concerns?

  • Overlays can deliver much of this value, however it is worth noting that we are seeing enterprises deploy overlays and underlays in the same environment. The SDN underlay transforms how the network is operated while the overlay transforms how systems engineering provides connectivity to virtual infrastructure.
  • Also, early adopters have identified network visibility as a key challenge with overlays. Their top three challenges are “control plane and data plane visibility,” “end-to-end visibility across physical and virtual network elements” and “end to end troubleshooting across physical and virtual network elements”
  • Bare-metal workloads are still abundant in most enterprises. While overlay vendors have made progress with switch gateways that can incorporate these physical workloads into logical networks, this is not a mature part of overlay solutions.