Hi, I am interested in hearing the approach and thought-process that senior people on NANOG are following when presented with an NFV solution. Assuming that the exercise at hand is to consider NFV for future expansions of Firewalls and L3VPNs or stay with the existing model of what is called PNF (physical network function)...i.e : classic routers and FWs. There are a lot of factors to consider and Vendors will typically give their biased opinion, so i'm trying to get my head out of their game, to be able to think agnostically about the whole thing. 1) Product and Service/Support Cost. 2) Operation Complexity/Learning Curve. (open source products included). 3) X Factors (Those that are never listed but do bite in the back) : Quality, Integration with Classic, Migration, Usability...etc The main goal behind us exploring NFV is the promised cost-saving, so a good method to be able to do the math of whether NFV will save opex/capex or NOT is definitely needed here and i'm trying to gather guidelines from the list. I think its easier to keep this post high-level, and later dig deeper. Cheers, K