Editor's note: In the first part of this series on Gartner's Data Center Networks Magic Quadrant, we explored the deep divide between Cisco and VMware's approach to SDN and data center control. In part two, we see how users respond.
Gartner's Data Center Magic Quadrant highlights the deep philosophical differences between Cisco and VMware in their SDN battle for data center control. Now network engineers are waiting to see what becomes of this divide -- they've hopes and doubts about both approaches.
"[VMware] is trying to pull the intelligence out of [the physical network] and move it into overlays," said Bob McCouch, network architect for a network consulting firm. "That makes sense from the perspective of their products. I have reservations about how that's going to play out in an operational model where you now have to troubleshoot two networks on top of each other."
"With ACI, I'm also a bit of a skeptic," McCouch said. "The idea of abstracting network configuration to a policy server that automatically identifies applications sounds really cool on paper. But I struggle to see how that will cost-effectively benefit customers at the medium end of the market. It seems almost like they are overreaching."
To some extent, even Cisco will have to incorporate some manner of overlay into ACI to account for workloads that aren't connected directly to Nexus 9000 switches. The vast number of other Nexus switches, which do not directly support ACI, aren't going away any time soon. However, today the choices are starkly different: VMware's software-only overlay or Cisco's hardware-centric approach.
"I agree on overlays in concept, but I'm still not sold on software-only overlays," said Brandon Mangold, network architect for United Airlines. "I think overlays are the future. More accurately, we need another layer of abstraction to achieve the desired flexibility."
Until this VMware-Cisco SDN struggle is settled, data center networking buyers will be in a "heightened state of confusion," according to Gartner's Fabbi.
"In the past, the demarcation between vendors was pretty obvious," he said. "In the traditional environment, you have influencers in silos -- Cisco predominant in networking, EMC for storage, VMware for virtualization, and maybe IBM for services and HP or someone else for servers. Now, all of a sudden, those lines are blurring, especially with Cisco and VMware, who are very dominant in their respective areas and [are] saying, 'We have very conflicting approaches to how we are moving forward.' It leaves customers in an awkward position."
Fabbi continued, "In some ways it's healthy for the industry, because every time we get healthy debate on architectural approaches and ways of doing things better, it's good for the industry. In the short term, it creates a bit of confusion."