Optical/IP Networks

Corvis Eliminates EDFAs

Corvis Corp. (Nasdaq: CORV) today announced two new products targeting regional networks and submarine cables (see Corvis Expands Product Portfolio).

The products aim to carry up to 800 Gbit/s per fiber on cables with no intermediate amplifiers for distances of up to 350 kilometers. The CorWave XL supports terrestrial connections and the CorWave XF supports point-to-point and festoon subsea connections. Festoon refers to applications where subsea cables are looped along a coastline, linking multiple landing points.

Corvis says that it will ship these products in the second quarter of this year, and that they mark a real breakthrough. Its press release quotes Andrew McCormick, a senior analyst with Aberdeen Group Inc., saying that Corvis is “first to commercialize Raman amplification.”

It’s “disruptive technology,” according to a quote attributed to David Huber, Corvis’s president and CEO, in the press release. It will enable Corvis to target new markets and new potential customers, it says.

At first glance, all of this may seem a little confusing from two points of view. First, Corvis’s existing products have already been used in trials demonstrating that optical signals can be carried over much longer distances -- up to 4,000 kilometers -- without needing regeneration (see Corvis Drives 4,000 Kilometers...).

Second, established vendors of submarine cable systems say the use of Raman amplification on unrepeatered subsea cables isn’t new. It was first demonstrated six years ago, when STC Submarine Cables -- now part of Alcatel SA (NYSE: ALA; Paris: CGEP:PA) –- showed a system driving 16 channels of 2.5 Gbit/s over a distance of 426km at the European Conference on Optical Communications (ECOC) in 1995. The demo was repeated over a distance of 511km at the Optical Fiber Conference (OFC) in the same year.

Alcatel has now installed a commercial system of this sort in Canada, according to Eric Brandon, manager of Alcatel’s unrepeatered system design team. In lab experiments, Alcatel has already demonstrated a system carrying 32 channels at 40 Gbit/s over 250km and plans to unveil a system carrying one terabit a second over 350km at OFC next month.

Other submarine cable system vendors have also developed Raman amplication products. NEC Corp. (Nasdaq: NIPNY), for instance, says that it can already do 640 Gbit/s over 350km.

However, Corvis’s claims stand up to scrutiny on closer inspection.

Here’s the score. Nowadays, most of the fiber that's installed on long-haul routes incorporates EDFAs (erbium doped fiber amplifiers). The EDFAs are sections of special fiber that are spliced into the normal fiber every 60 to 80 kilometers. The outer cladding of the fiber is pumped with light from a local laser, and this boosts the power of the actual signal passing through the core.

Raman amplification works on a similar principle, but in this case, there’s no need for special fiber.

The distance records of thousands of kilometers that Corvis (and other vendors) have achieved are over fiber fitted with EDFAs. The new products unveiled by Corvis achieve a maximum distance of 350 kilometers without EDFAs. That's the key point.

Likewise, the records claimed by Alcatel for Raman pumping over unrepeatered subsea systems are for fiber that incorporates “at least one EDFA” according to Marc Fullenbaum, an Alcatel product marketing manager. The “unrepeatered” term refers to the absence of electrical regeneration of the signal, not the absence of EDFAs.

The lab experiment that Alcatel will report at next month’s OFC carried 100 channels of 10 Gbit/s over 350 kilometers of fiber incorporating one EDFA. Corvis says that its new products will support 320 channels of 2.5 Gbit/s or 80 channels of 10 Gbit/s over the same distance, with no EDFAs. Right now, this is a claim. It’s yet to be proved in trials.

So, is eliminating a single EDFA such a big deal? It probably is, in that EDFAs involve putting power down the cable to power the lasers that drive them. “It’s not cheap,” admits Fullenbaum. Having lasers at the bottom of the sea also raises questions about reliability.

-- Peter Heywood, international editor, Light Reading http://www.lightreading.com

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LightBeating 12/4/2012 | 8:56:19 PM
re: Corvis Eliminates EDFAs I'm not surprised that LightReading publishes an other negative article on Corvis. However, interested readers should note that there is a vast difference between a lab experiment and a commercial product. For example, The Corvis Corwave product, transmitting up to 800 Gb/s on 3200 km has been demonstrated by research groups all over the place, but yet Corvis is the only company that can install it in an actual installed fiber network.

In this article, LightReading does not cite any product that is commercially available and would be similar to Corvis' announcement, apart from the vague NEC reference (I didn't know NEC was a major player in the long distance DWDM game). The Alcatel installed product has much smaller capacity.

I don't expect this Website to be objective any more, however, if we are allowed to post messages, then at least I have a chance to give a different point of view!
hiro 12/4/2012 | 8:56:17 PM
re: Corvis Eliminates EDFAs Hi Lightbeating and all others,

in which way are Corvis' products better than other company's? I'm especially interested in your opinions on the new CorWave products.

As many other investors (I own some Corvis shares) I don't really know what to think, since Corvis doesn't exactly release detailed technical specifications of it's products, how they work and where their advantages are.
lightreading 12/4/2012 | 8:56:16 PM
re: Corvis Eliminates EDFAs LightBeating, guess what? Nobody cares anymore. If the Corvis makes product that are superior, they should talk about it. They don't, at all. And niether do the two customers that they have. That tells me they have nothing special. In my mind they aren't much farther out of the lab than anyone else.

They're not winning new customers, the customers they have don't talk about the products, and the company itself doesn't talk about the products - the end result is, the company dissapears off everyone's radar. You're worried about objectivity? Pretty soon Corvis releases won't even get covered.

At first I thought Huber was a genius for starting Corvis and being secretive. Now it is clearly obvious he's an idiot. They are now trying to live up to the astronimically huge expectations they have created for themselves. As the market has already demonstrated, Huber is in over his head.

Peter Heywood 12/4/2012 | 8:56:15 PM
re: Corvis Eliminates EDFAs LightBeating, just wanted to clarify one thing that you raised, and which probably confuses a lot of folk (including me to start with):

Corvis's existing products target ultra-long haul transmission over fiber that incorporates amplifiers every 40 miles or so. This is the stuff that goes 3,200 km etc.

These new products, announced today, go 350-km over fiber that *incorporates no intermediate amplifiers*. That's the key thing. This is a totally different cupa tea. The distances in this case are much less for everybody.

You have to be careful about comparing like with like with this stuff.


Peter Heywood 12/4/2012 | 8:56:15 PM
re: Corvis Eliminates EDFAs Corvis says it has an explanation of why its products really are an advance on the ones from Alcatel, NEC etc.

If I get sufficient info to check this out, I'll post an update.

Peter Heywood 12/4/2012 | 8:56:15 PM
re: Corvis Eliminates EDFAs Furio, I asked Corvis whether these developments came from Algety and was told that they weren't, they were a derivitative of Corvis's "home grown" technology.

I talked to Scott Clavenna about this, who thought it sounded really strange. He pointed out that Algety had products targeting exactly the same markets as these products. He couldn't understand why Corvis wouldn't use them and would develop some other products instead.

Peter Heywood 12/4/2012 | 8:56:14 PM
re: Corvis Eliminates EDFAs 40 miles or so between amplifiers
Optiker 12/4/2012 | 8:56:14 PM
re: Corvis Eliminates EDFAs Peter,

did you mean 40 or 400 miles between amplifiers?

photonic314 12/4/2012 | 8:56:13 PM
re: Corvis Eliminates EDFAs Step into my "way back machine" back some 25 years ago to a Rock band screaming out lyrics that go something like..."Paranoia, please destroy ya or Paranoia will destroy yaG«•G«™well something like that! Forgive the inaccuraciesG«™IG«÷m the one on the Subway that bastardizes lyrics to popular songs!

Go Forward in the machine to mid 1980G«÷s where scientists at a company in Cambridge, MAG«™one known for instant picture film, invent develop and patent certain Raman Amplification Technology, of which the likes of SDL, Lucent AT&T and others (hint) eventually license and use for their now famously hyped Disruptive Technology!

Go forward still to Supercomm 2000 Atlanta Ga, where David G«£CIA OperativeG«• Huber is guarding his oversized, under-detailed booth that is filled with colorful back drops, wrapping around 3 smoked colored plexi-glass facedG«™.RacksG«™.I guessG«™for all I know they could have been vending machinesG«™the only thing missing was the mirrors, and I donG«÷t mean MEMG«÷s!

A poor unsuspecting Asian women (yes camera in hand), walking along the runway between boothG«÷s decides to take a picture of a colleague, (note, back to Corvis booth)G«™fell victim to the G«£rent a copG«• want a be, (Huber), when he silently announced on his hand Mic (SWARM, SWARM a.k.a. Seinfield). She was summarily whisked away to the interrogation roomG«™(Is It Safe!!!)

CorvisG«÷s only enabling technology is that they have found a way to dupe the entire optical community in thinking that they may have something novel! Note: they said they had the all optical system designed and ready for deployment before buying AlgetyG«™so why did they buy Algety?

Last question! What does their system cost? After dispersion management, smoke and mirror designs, unoriginal concepts, I would guess that putting repeaters back in the system might save carriers some money!!! I exaggerate, ofcourseG«™I donG«÷t want all you Corvis faithful, you know the ones, that bought in at 90, then double down at 50, then did it again at 20G«™to think I am Corvis bashingG«™Its just that I think its okay to be stealthy when your starting out, hell its recommendedG«™but when youG«÷re a public company, and you make the concept of secrecy into a mission statement, that becomesG«™well, alarming!

iprsvp 12/4/2012 | 8:56:12 PM
re: Corvis Eliminates EDFAs Guess what these are not really new
products. They are JUST "tampered"
version of their regular cor wave

Looks like they are running out
of options.
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