This is another one of those hypothetical questions. I've been trying to figure out whether or not having a faster 'segment' of a network in between host A and host B will translate into a faster flow rate or lower latency between them. Let me show you the physical links in the network between computer A and computer B:
host A (1000Base-T NIC) -> copper 1000Base-T link -> 1G copper switch ->
[SFP module] -> a short 10G/40G/100G fibre run -> [SFP module] ->
1G copper switch -> copper 1000Base-T link -> host B (1000Base-T NIC)
In short, there is a 1G link from host A to the first switch, which has an SFP module in it connected to a short 10G/40G/100G (doesn't really matter, just faster than 1G) fibre run, which connects to another SFP module in another 1G copper switch, which is connected via 1G copper to host B.
Does traffic flow faster between the two hosts because of the fibre run in the middle? Or would the flow rate and latency be the same if the section between the two switches was the same speed as the rest of the network?
It would make sense for latency to be lower between host A and host B, but the ingress and egress rate of the NICs would limit the flow rate, correct? If this is so, does it make sense to connect 'core' switches and routers together with faster links?