Centralization seems to be the current "silver bullet" for network complexity — but will it really "solve" for complexity, or just bring us another round of "pushing complexity around?" This presentation considers an alternative view of the centralization/decentralization debate. - See more at: https://www.nanog.org/meetings/abstract?id=2571#sthash.QlDGUQ1K.dpuf
Noticed over the years that we keep adding layers to try to manage complexity. But we end up doing roughly the same things over and over again at each layer.
Why not lose all the layers and drop the whole mess into the control plane? Just layer the control plane. (VXLAN?)
Theory is that the control plane already has the best possible scalability protocols for reachability etc. - BGP, etc.
Where does it make sense to have an API vs a protocol?
Can polling ever outrun local reaction to an event? No. Local reaction is always faster.
Should policy be expressed in terms of forwarding?
Is a unified view of the network actually possible? We may be getting to the point of using heuristics vs algorithms.
What should be do about failure domains?
Are we ready to throw away 20+ years of experience to "try something new" (totally centralized -- his answer is "no")
Basically he is in favor of decentralization and not SDN.
Whither forward? Support YANG/NETCONF and I2RS
Think about existing protocols for southbound: BGP, PCEP
Has lived through "centralization vs decentralization" several times and thinks it is the wrong debate.
Dave Meyer: Is complexity always a bad thing. But if you want robustness, you need complexity. It is gratuitous complexity that you don't want. Try to understand what complexity is adding robustness and what isn't. Discussion about layering is on-target. Layering is one way to build the good type of complexity because it helps you to isolate and understand.
Control of complexity comes down to policy dispersion - who controls and where?
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