Per Hansen of Ciena at
NANOG 50talked about
growing capacity not by adding more
data cables under the sea, rather by increasing spectral density.
Eventually new cables will be needed, but meanwhile he thinks
we can get up from about 2 bits to to 5 or 6 bits per Hertz.
It does require more power: same energy per bit, but more bits.
Plus mesh networks for rerouting, even if it means rerouting
backwards around the world, he notes.
We’ve observed that sort of emergency backwards routing
as long ago as January 2008, in the
U.A.E. Cable Cut.
Here’s an example of some Internet routing in Iran, in this case on the way to the Ministry of Foreign Affairs on Monday 15 June 2009. Normally, routing and latency don’t change much.
Starting Saturday 13 June, the day after the election, routing and latency
have become increasingly disturbed. More here.