Fiber nets replacing switches?

[deanwebb]

http://blog.fibermountain.com/blog/fiber-mountain-and-facebook-fabric-networks-similarities-and-differences

One thing's for sure, if something is cheaper to do and pretty much as effective as a costlier alternative, the cheaper thing will be done.

[routerdork]

I'm getting confused the more and more I read about current DC trends. Have we gotten to the point in time where routing speed is so fast we care less about switching? I was always taught to think like this "switch everything you can, route only when you have to" Is the idea of a Spine/Leaf that much different from Core/Aggregation/Access? Topology wise it looks the same to me.

[AnthonyC]

Actually topology is very different; the traditional way doesn't scale well and is inefficient for network pathing (even if using ECMP).   Also for SDN the POD design is much more suitable for its simplicity and scalability.  At scale all these inefficiency matters a lot.

[deanwebb]

I wonder if this will make a transition to the network perimeter... or what it would look like at the perimeter. There's basically a path to the datacenter and a path to the Internet... if you don't need device-to-device communication, you should be good.

Or does that mean device-to-device communication has another way to work?

I'm now wondering about voice applications...