We’ve been getting a lot of great questions about ACI since our launch as people try and better understand the value of an application-oriented approach. I got the following questions on my blog post about the Application Virtual Switch that probed on some of the thinking behind an application-aware architecture, and why now was the right time to release it (after all, John Chambers called it the most disruptive Cisco innovation in a decade!). Anyway, on to the Q&A:
I’d like to know more about the path that Cisco pursued to evolve towards an “application aware” architecture. This back-story (how Cisco arrived at this juncture) would be very helpful to industry analysts, customers and institutional investors. Here’s some of the key questions on my mind.
- What were the primary roadblocks that inhibited the adoption of this innovative approach in the past?
I would say that the Application Centric Infrastructure (ACI) was a combination of a Eureka! moment, that people just never thought of it before, and that it was also an insightful evolution from early SDN technology. So, it might be fair to say that SDN had to come along, and then we realized, here might be a better way to program the network (with an application-oriented model, rather than a network-centric model).
That might be another way of saying that the lack of SDN as a precursor to ACI was a roadblock. But I think of it as networks were just built on hardware that were optimized to pass packets and other very specific tasks. And the limitations of historical networking protocols and traditional network designs, coupled with very limited ways in which you could manage a network and tell it what to do, all served as roadblocks to implementing anything like ACI. So the roadblocks that had to be cleared included the ability to program switches through software interfaces, and to centrally manage the software applications or controllers to orchestrate the broader network, not an individual device. Those are some of the things SDN brought along.