In reply to Bill.

Thank you. ACI can offload policy to hardware, support integrated underlay-overlay with nexus 9K and can also work in overlay fashion over Nexus 2K/5k/7k/9K. Also, for brownfield use case, we can extend ACI policy by adding physical remote leaf ( when you have the flexibility to put Nexus 9K) or put vPOD and extend the policy where you don't have flexibility to put world class, performant, cost effective Nexus 9K.