Costs
Whenever I tell project managers how much 40G SFP cost they go pale and ask for 10G.
It's not the cost of the switches that's killing adoption and remember you need them by the dozen.
... then there's 100G
Cisco will retire its Nexus 6000 switches in mid-2017. The company recently popped out a end-of-life notice for the switches, which were launched in 2013 as part of a push to encourage adoption of 40G Ethernet. These days Cisco is keener on 100G Ethernet, promising to sell you faster kit for the same price as 40G kit. With …