Perhaps FTTH wasn't all that good an idea, after all?

[David Farber <dave () farber net>]

Begin forwarded message:

From: Randall <rvh40 () insightbb com>
Date: October 12, 2006 12:06:24 AM EDT
To: dave () farber net, dewayne () warpspeed com
Subject: Perhaps FTTH wasn't all that good an idea, after all?

http://htdaw.blogsource.com/post.mhtml?post_id=391107

Thursday, October 12, 2006 at 12:02 AM EDT
Imagine that you're the guy who has to deliver the bad news. You  
straighten your tie, clear your throat, and jangle your keys as you  
step into your boss's office. She does not look like an executive who  
has gone to the sorts of conferences where managers are reminded not  
to shoot the messenger. It is, in fact, quite possible to imagine her  
stashing a Glock just out of sight in a desk drawer. Come to think of  
it, it's been months since you've seen Jenkins, the last guy to  
deliver bad news. "Boss," you begin, "about that $18 billion we just  
spent? Well, turns out it wasn't strictly necessary..."

It's a conversation that could be playing out at telcos like Verizon  
in the next few years if a new consortium of hardware vendors and  
phone companies has its way. The group is led by ECI Telecom and  
includes members like Spanish telephone giant Telefonica, but it's  
based in Israel and funded in part with a grant from the Israeli  
government.

The group's goal is audacious: achieve fiber optic speeds over copper  
wire. If they succeed, Verizon's $18 billion decision to run fiber  
all the way into consumers' homes might be a costly one for them and  
other companies around the world that have jumped on the fiber optic  
bandwagon.

The group hopes that the answer will be found in the use of Dynamic  
Spectrum Management (DSM) to boost DSL speeds. "The main obstacle for  
the advancement of DSL technology is the interference ("crosstalk")  
generated from different DSL lines that share the same telephone  
cable binder," said Professor John Cioffi, Professor of Engineering  
at Stanford University, a pioneer of DSM research. "DSM is a  
promising technology for the future evolution of broadband access  
networks using existing copper infrastructure."

To avoid interference, current DSL implementations use static  
spectrum management that is built for a "worst-case" scenario. Most  
actual phone lines would allow for far better performance, and DSM  
technology will allow each DSL connection to be regulated in real  
time by the hardware based on measured crosstalk and on current data  
needs of each customer. The end result could be DSL connections that  
top out at 100Mbps or more.

More bandwidth than fiber?

One of Dr. Cioffi's presentations of DSM contains a slide that argues  
that copper actually has more available bandwidth than fiber; it just  
needs to be better used. He points out that a bundle of 50 Cat 3  
twisted-pair wires (the kind that might be used in the last segment  
of the phone network) has 10Gbps of available bandwidth to distribute  
to the fifty homes at the end of those wires. By contrast, fiber to  
the home has only 2.5Gbps to distribute to its homes.

"DSM is the next step in the evolution of telco's access  
infrastructure. It will allow telcos to provide high-bandwidth  
services cost-effectively by leveraging FTTC (fiber-to-the-curb)  
topologies rather than replacing all copper wires with fiber-optics  
until the subscriber premises (fiber-to-the-home)," said Zvika  
Weinshtock, VP of Marketing for ECI's Broadband Access Division.

It's not hard to see why this technology would interest telcos. Many  
have moved slowly on FTTH deployments over cost concerns. Others,  
like Qwest, have decided to remain on the sidelines. DSM, should it  
provide good real-world results, could keep the existing copper  
infrastructure competitive for many more years, and could give DSL  
users massive speed boosts, something welcome to power users who  
might cast a lustful eye on faster FiOS or cable modem connections.

While Verizon has made a big bet on FTTH, don't call the money wasted  
just yet. The commercialization of DSM is just beginning, and real- 
world results may never jibe with laboratory experiments. For the  
forseeable future, FTTH still offers the fastest available speeds.


http://arstechnica.com/news.ars/post/20061010-7952.html




My Original Writing blog: http://itgotworse.blogsource.com



-------------------------------------
You are subscribed as lists-ip () insecure org
To manage your subscription, go to
 http://v2.listbox.com/member/?listname=ip

Archives at: http://www.interesting-people.org/archives/interesting-people/