VMware says more than 50 of its NSX customers have invested more than $1 million in the platform, which VMware says is an indication of how strongly customers are willing to commit to the product.

It's hard to gauge just what $1 million buys you. (The figure wouldn't include any networking equipment that NSX rides on.) But it represents "a deep level of commitment," says Martin Casado, senior vice president of VMware’s network and security business unit. "This is not something you're throwing in as a demo or a PoC [proof-of-concept]."

VMware feels particularly good about the number because NSX isn't tied to any of VMware's other products.

NSX isn't bundled with ESXi or the vCloud suite, nor do customers get a discount on vSphere when they buy NSX. In other words, VMware can claim that all of its NSX customers — more than 400 as of December — bought the platform because they actually wanted to use it.

You could consider that a dig at Cisco, whose early counts of Application-Centric Infrastructure (ACI) customers included those using the Nexus 9000 switch "standalone," without any software-defined networking (SDN) attached.

Cisco says it now has 300 customers for the Application Policy Infrastructure Controller (APIC), the key element that puts some SDN into ACI.

Customer count aside, NSX has been shipping in production for about a year and a half. The product is a long way from the days of having to explain what SDN was.

"I feel like for the last six months, we've been focusing much more on deep operationalization than on the CTO thing," Casado says. That's been reflected in his own change of job; he started out being the CTO behind NSX and is now focused on the business side of the product.

Having customers in production gives VMware the chance to develop more uses for NSX. Security, through NSX's inherent microsegmentation of the network, was one.

Now, the company is also looking at using NSX as a disaster recovery tool. In the event that an entire data center goes down — think natural disaster — NSX could move a workload to another location. It's a use case VMware has been focusing on lately, Casado says.