Researchers Transmit Optical Data at 16.4 Tbps 2550km

Stony Stevenson writes "The goal of 100 Gbps Ethernet transmission is closer to reality with the announcement Wednesday that Alcatel-Lucent researchers have recorded an optical transmission record along with three photonic integrated circuits. Carried out by researchers in Bell Labs in Villarceaux, France, the successful transmission of 16.4 Tbps of optical data over 2,550 km was assisted by Alcatel's Thales' III-V Lab and Kylia, an optical solution company. The researchers utilized 164 wavelength-division multiplexed channels modulated at 100-Gbps in the effort."

Translation please?

What's that in Library-of-Congresses per fortnight?

Re:Translation please?

Is that a laden European or African library of congress?

Re:Translation please?

(14 * 24 * 60 * 60) / (20 / 2.2) = 123,984 LoCs/fortnight

(total seconds per fortnight)
14 days per fortnight
24 hours per day
60 minutes per hour
60 seconds per minute

all over

(seconds per Library of Congress transferred)
20 terabytes per second (one LoC/second)
2.05 terabytes per second (16.4 terabits per second

Re:Translation please?

I saw "LoC" and thought "Lines of Code"; my second thought was that you have some *mad* job security.

Re:Translation please?

What's that in Library-of-Congresses per fortnight?

Well... if you are Concast they will give you those numbers in terms of photos or mp3's or emails downloaded in a month.

Personally I like to know in terms of how many 8 track tapes I can download a month. ;-)

Re:

HD DVD, Bluray or regular?

Re:

Data per boeing 747 (LCF version)

DVDR = 159238213.7 GB/747LCF
HDVD = 677609420 GB/747LCF
BDVD = 847011775 GB/747LCF

-nB

So, this speed, on a scale of 1-10...

Would this qualify as 11?

ObWalken

<walken>That's a lot of cows. [imdb.com]</walken>

Don't get too excited.

That's just BURST throughput. Depending on factors like time of day, how many other users there are, and environmental conditions, throughput may drop as low as 33kbps. And we do NOT filter bittorrent.

Just check your TOS agreement. It's all right there.

Re:Don't get too excited.

Now offering the fastest 16.4 Tbps service* available anywhere

*1 Gig upload/download monthly limits apply

maybe its just me

"164 wavelength-division multiplexed channels modulated at..."

how very Star Trek of them.

Re:maybe its just me

"164 wavelength-division multiplexed channels modulated at..."
how very Star Trek of them.

I'm sorry Captain, but we canno' reach these speeds with time-division multiplexing. the phase coils canno' handle it!

Doesn't matter...

No matter how much speed they create, they will still be subject to the Law of Diminishing Porn Returns, which states:

For download rate n, my demand for new porn will require me to download at a rate of n+1.

Re:

Surely if an ISP adopted this, they'd have people signing up left right and centre. Wouldn't it be awfully attractive to their target audience?

Re:16.4 Tbps of optical data?

They had 164 lasers with different colours sending 100 Gbps EACH over the same fiber, splitting the colours apart again at the other end with what probably is a little more advanced than a prism.

Re:16.4 Tbps of optical data?

Its called dense wave division multiplexing, or DWDM. You take independent links (in this case 100Gig links), and transmit each of them on a slightly different wavelength of light called a Lambda. Since optic is looking for a specific wavelength, you can now run many "virtual links" per physical fibre. This is the standard technology for most Telcos. The innovation here is that they are doing this with 100Gig transceivers, and they have chipsets fast enough to combine the different lambda's back together into on high speed link. And yes, you can now let the Lambda Lambda Lambda jokes fly

Re:

If you really need greater than 10Gbps then go with Infiniband as you can get 12x HCA's that will do 24GBps (48Gbps full duplex). But if you're paying $50 for 10Gbps ethernet you're not getting offloading and your CPU's are probably swamped of your TCP/IP

Re:Make it Short and Fast and Snappy

There is another problem, and is actually the bottleneck of transmitting packets at high rates.

It doesn't really matters (yet, and considering Ethernet technology) if the BW of the fiber is a zillion Petabits/sec.
The problem is now at 1Gbps and 10Gbps in Ethernet technology, and is because the processor overloads with the amount of hardware interrupts. The processors that are general purpose have to waste too many clock cycles processing that much interrupts, the processors nowadays are superscalar [ http://en.wikipedia.org/wiki/Superscalar [wikipedia.org] ]and every time the processor have to change the context (to attend an interrupt) has to do lots of things like unloading the registers, saving the context, loading the registers of the new process, and has to drop something out of the pipeline [ http://en.wikipedia.org/wiki/Pipeline_(computing) [wikipedia.org] ] loosing performance.

Ethernet tech has a huge latency [ http://en.wikipedia.org/wiki/Latency_(engineering) [wikipedia.org] ] and a stack that makes processing not so easy (if you look at te code of a linux network device driver it handles pretty much everything including writing the mac address that is only copied when the driver initialize).

That is why there are some relative new things (NAPI in Linux) that try to make lessen the overload, there are new network devices that handle layer 2 and 3 (or at least parts of those, for example, is used to be handled the checksum algorithm) to avoid doing it in the processor. There are some white papers (one from intel, another from NetXen, I'm sorry I don't have the links now) that explain the problem and some approach to a possible solution.

Yes, I know, there is something I have not said, and is that the main switches or routers have to deal with that and have hardware specially designed to do heavy network packet processing, and that is the point, the network cards will have to do that (and are already starting to), neither is an easy job for hardware designers, nor for the market, is easier and cheaper to have a machine that you can change the behaviour only changing the firmware or changing settings from a program (routers have an operating system, and lots of those are a general purpose microprocessor with a linux kernel and a web server to configure it, for example home routers).

There is much to say yet in this field.

Re:

Interrupt loads can be greatly reduced by switching to a polling-driven architecture. See FreeBSD.

Re:

>Interrupt loads can be greatly reduced by switching to a polling-driven architecture. See FreeBSD.

New API (NAPI) takes a mixed approach, read: [ http://en.wikipedia.org/wiki/New_API [wikipedia.org] ], and for more information: [ http://www.linux-foundation.org/en/N [linux-foundation.org]

Re:

This is the reason 100gpbs isn't being considered for lan use. It just isn't feasible at this point.

Stick a thousand machines on each end, and you'll understand why 100Gbps is needed.

Re:

I'm running Linux on a Playstation3 with SPU video drivers in its Cell uP that can run at over 150GFLOPS. Since the PS3 has only 512MB RAM, it needs to be fed by the LAN and just buffer the LAN in its RAM. Even if SATA drives are delivering only 1.2Gbps, t

Re:

The problem has never been the glass! There is absolute craploads of dark fiber just about everywhere. Last time I saw stats it was something like less than 1/3rd of installed fiber was lit up. It's the uber expensive routing equipment needed to keep up wi

Re:Sending "optical data"

Senator Stevens? Is that you?