[LINK] FTTH? Doesn't Look Likely...

[Craig Sanders]

here's one of the reasons why fibre is better in the long term for
everything but mobile applications (but that's not an either/or
situation - they're complementary not mutually exclusive technologies,
serving quite different needs).

the research described in the article below is a long way off being a
usable product - it just highlights the incredible potential of optic
fibre networks. if you have the fibre infrastructure (whether FTTN or
FTTH) in place, you can easily upgrade the routers to take advantage of
the faster speeds.

more significantly, as a shared medium (rather than point-to-point like
fibre), there's no way any wireless technology can even approach current
fibre speeds, let alone future speeds.

the optic fibre being installed in the ground now is good for at least
25-50 years. there will be numerous upgrades in switch/router bandwidth
before it becomes too degraded or too obsolete to be any further use.

and with sufficient fibre bandwidth, constructing a complementary
wireless network is a much simpler exercise - a short-range (eg <= 1km)
high-speed wireless node could be installed at, say, every 10th or 20th
premises.


http://www.extremetech.com/article2/0,2845,2385134,00.asp

May 10, 2011 -By Sebastian Anthony

Graphene-Powered Optical Networks Could Lead to Petabit and Exabit Transmission Speeds

New research published by the University of California, Berkeley, shows
that graphene -- an incredibly thin and flexible form of carbon --
can be used to boost the transmission and switching speed of optical
modulators, the building blocks of routers that form the backbone of the
internet.

Scientists at UC Berkeley, led by professor Xiang Zhang, have found that
one-atom-thick layers of graphene can switch light on and off incredibly
quickly. With just the right amount of positive voltage, graphene
turns opaque, stopping any light from passing through -- and with a
negative voltage, graphene can be turned transparent again. The team
then successfully shrunk a graphene optical modulator down to 25 square
microns in size -- small enough to include in silicon circuitry -- and
modulated it at a speed of 1GHz. The researchers say that modulation
speeds of up to 500GHz are theoretically possible, though -- and for
comparison, the modulators found in 40Gbit switches are measured in
centimeters and operate at just 40GHz.

It doesn't end with faster switching speeds, though. Graphene, unlike
current modulators, can absorb -- and thus modulate -- an incredibly
broad spectrum of light, from ultraviolet through to infrared. In other
words, with every on/off pulse, a graphene modulator can transmit a huge
amount of data using spectral bandwidth that conventional modulators
can only dream of. Professor Xiang Zhang, in an attempt to boil his
group's new findings into consumer-speak, puts it this way: "Instead
of broadband, we will have 'extremeband.'" -- if graphene modulators
can actually operate at 500GHz, we could soon see networks that are
capable of petabit or exabit transmission speeds, rather than megabits
and gigabits.

Graphene, if you haven't heard of it before, is a crystallized form
of carbon that is something of a "wonder material." It's incredibly
cheap to make, and it also happens to be the thinnest and strongest
crystalline material in the known universe. It can be easily extracted
from graphite, the substance used in pencil lead, and, to top it all
off, graphene is a good conductor of heat and electricity. All of
these factors combine to make graphene not only an excellent optical
modulator, but also a prime candidate for future advances in silicon
chip lithography.

These graphene optical modulators are the real deal -- they're not some
flash in the pan research project that will fizzle into the digital
ether. We could see graphene-powered core routers within a few years,
and after that, it won't be long until graphene modulated communications
find a place in just about every kind of digital interconnect.

Read more at UC Berkely News Center

craig

-- 
craig sanders <cas at taz.net.au>

BOFH excuse #157:

Incorrect time synchronization