Continuing on its tradition of contributing and committing to open source and open standards over the last 25 years, today Cisco announced “OpFlex” – a new open standards-based protocol for Application Centric Infrastructure that has been submitted into the IETF standardization process. We believe this will accelerate multi-vendor innovation in data center and cloud networks to drive operational simplicity, lower costs and increased agility.

Why is this required?

Traditional SDN models today function on the basis of an imperative control model with a centralized controller and distributed network entities that support the lowest common denominator feature set across vendors such as bridges, ports and tunnels. As the network scales, the controller becomes a bottleneck due to the need to maintain increased state, and starts to impact performance and resiliency. Likewise, because the applications, ops and infrastructure requirements need to be translated into network configuration, it impacts agility and introduces a manual learning process, requiring app developers to describe their requirements in low-level constructs.


If we contrast that with the vision of the ACI model with the Application Policy Infrastructure Controller (APIC), ACI adopts a declarative management approach. This model abstracts applications, operations and infrastructure providing simplification and agility. By distributing complexity to the edges, it also increases better scalability, and allows for resiliency – i.e. the data forwarding can still continue to happen even if there is no controller. It further provides ease of use with self-documenting policies automatically deployed or cleaned up from devices as necessary. All of these help circumvent the issues seen in traditional SDN models.

For this declarative model to work across a multi-vendor environment, to translate and map policy definition into the infrastructure, there has hitherto been no standard protocol to do that across physical/virtual switches, routers and L4-L7 network services. This vacuum has led to the development of “OpFlex” – a new open standard recently submitted to the IETF.

Who is contributing to OpFlex?

Several industry leaders and practitioners are actively involved in the standardization process. These include Microsoft, IBM, Citrix and SunGard Availability Services, in addition to Cisco.


Is there an Open Source Element to this?

Yes, Cisco is working on an open source OpFlex agent implementation that can be embedded in devices to support the OpFlex protocol. This agent will initially be designed for Open vSwitch but will be reusable across platforms.

Which vendors are supporting OpFlex?

A number of leading technology vendors have committed to supporting OpFlex in their products. These include Microsoft, IBM, F5, Citrix, RedHat, Canonical, Embrane and AVI networks. Additional vendors are expected to come on board across the networking landscape.

Where can I find more information?

A number of the partner blogs are included in the official press release here. You can also learn more about OpFlex by reading the IETF draft.  Over the next few weeks, we will continue to bring in additional perspectives from several thought leaders among the ecosystem partner community.

If you’re in Las Vegas attending Interop we invite you to join us for the customer luncheon session at In 1PM PST. If you  are remote and would like to join the online webcast – “New Applications are Knocking! Is your Data Center OPEN for business?”, we welcome you to Register Here!

You will see Cisco customers, partners and executives come together to share their perspectives on building out Application Centric Infrastructure.


Shashi Kiran

Senior Director, Market Management

Data Center, Cloud and Open Networking