Copper WANs aren't going away
So carriers and others are seeking new uses for them - such as Ethernet.
The mobile data 'bump'
It's not just offices that are driving the need for metro or first-mile Ethernet though - it is mobile networks, and especially the need for more and more backhaul capacity to cellular base stations.
Even more specifically, says Olle Gustafsson, that mobile backhaul traffic is shifting from being TDM-centric to being IP-centric, as the network operators finally figure out how to sell mobile data services.
The problem is that in many cases they seem to have done it without adequate planning. It is not clear whether that was down to a lack of foresight, a shortage of money after investing in 3G, or a combination of the two.
But data volumes are rocketing at last, and many cell sites don't have the backhaul capacity to cope with the rate of growth - and that's going to provide a healthy boost for mid-band Ethernet, says Kevin Hatteras.
"We're now getting pulled into mobile backhaul - the operators are needing to upgrade fast to serve data," he explains, adding that "it's typically two to three T1s per base station, serving three or four carriers," which means about 1Mbit/s per carrier.
And as more and more of us move over to mobile broadband, that's going to make the idea of running 10 or 20Mbit/s over the same copper start to look awfully attractive.