The marketplace for enterprise IT is full of potentially disruptive technologies that are challenging the dominance of leaders in a number of areas. The clarion call in networking is that SDN will topple Cisco’s supremacy. VMware created the server virtualization market and is now under attack from both replacements (Hyper-V and KVM) and cloud alternatives. While Wikibon research shows that there is still growth opportunity for virtualization into mission critical applications, VMware has targeted networking as an adjacency for expansion. In 2013 we saw a lot of SDN announcements including VMware NSX and Cisco ACI; this article will examine how these two market leaders will shape the SDN discussion.

Networking upgrade cycles are typically among the longest of any equipment in an enterprise data center. While servers follow Moore’s Law and storage has regular updates to disk drives (and now flash is having significant impact on architectures), networking equipment can take a decade to adopt new speeds; if we look at 10Gb Ethernet adoption, the standard was ratified in 2002 and while most networking cores are now 10Gb, most edge devices (and approximately 75% of servers) are still at 1Gb. Of course new features and functionality can be delivered outside of speed upgrades, but as discussed at the Open Networking User Group, customers would like to see the creation of a networking software ecosystem. The promise of software-defined networking is more than just the separation of control-plane and data-plane – it should allow IT more agility with deployments and the integration of solutions from a broader set of application providers. This vision is still far from reality today. The OpenDaylight initiative will deliver a controller, but it is uncertain if it can deliver an open API platform that any software vendor can deliver applications through.

VMware NSX, Source: VMware
VMware NSX, Source: VMware

VMware NSX (the combination of VMware’s vCloud Network and Security with Nicira NVP – see Ivan Pepelnjak’s webinar for a deep dive) delivers overlay networking that supports multiple hypervisors and clouds across most hardware platforms. While there are no limitations on the VMware side, Cisco is refusing to provide interoperability with NSX and instead has put forth its own solution – Application Centric Infrastructure (ACI). Cisco has rallied a broad set of ecosystem partners including leading management and storage vendors. Cisco ACI requires that the hardware platform for its ACI (basically a Cisco-branded SDN offering) is only Cisco; specifically the new Nexus 9000 (which was created by the Insieme spin-in). Cisco’s data center networking switching portfolio now must justify and span three lines – the venerable Catalyst, Nexus 3k/5k/7k and the new Nexus 9k. Cisco’s word of wars and blocks from allowing its switches to be used with VMware NSX is a risky move. A high percentage of Cisco switching and UCS (a very high percentage – perhaps 80-90+) are deployed in VMware environments, so Cisco will get pressure from customers to play nicely with VMware NSX.

Cisco Nexus 9000 family, Source: Cisco
Cisco Nexus 9000 family, Source: Cisco

Fundamentally, VMware/Nicira attempts to disrupt networking by allowing virtualization administrators to extend into the networking space, while Cisco’s ACI strategy keeps the networking silo intact. Cisco ACI’s messaging of delivering more value to the application layer is a strong one, and VMware’s core services have been working this for some time. The adoption of SDN technologies is going to take years. VMware/Nicira’s Martin Casado (see interview from VMworld 2013) agreed that it is very early days for SDN.

A software-based solution like VMware NSX holds an advantage for early adopters who want to test out a solution versus Cisco’s ACI which requires the commitment of purchasing a new hardware platform. Service providers and large enterprises that act like service providers are also more likely to lean towards a software-based solution that gives them more flexibility on the hardware choice.

SDN does have potential to disrupt Cisco’s dominance, but Cisco is so good at marketing solutions and preparing the army of CCIEs that it is likely to keep ahead of the majority of users with a “good enough” solution for those who look to adopt SDN. As for VMware, while it will still be years before we know if the $1.26B bet on networking will pay off, it has vaulted itself further into the networking conversation than most of the traditional networking contenders have in the last decade.

Action Item: CIOs and IT teams must start the SDN discussion with an understanding of the strengths and gaps of the organization. IT has a tendency to allow existing relationships and inertia to prevent significant changes. If SDN solutions are successful, they can dramatically change the cost equation of deploying and managing the network, but there is not yet a clear leader or simple solution that users can rapidly adopt today. VMware and Cisco lead the conversation due to their respective market positions, but they should only be the starting point for SDN evaluation.