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Ethernet at 10 Gbps
An anonymous reader writes "This article talks about 10 Gigabit Ethernet and asks, 'But just how much data can a person consume?' Currently at work, we're working on a major project to re-architect our core application platform so that the different systems can be de-coupled and hosted separately. The legacy design implicitly relies on systems being in the same LAN due to bandwidth-expensive operations (e.g., database replication). Having this much bandwidth would change the way we design. What would you do with this much bandwidth?"
What would you do with this much bandwidth?"
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The company I used to work for was sending very high resolution images from multiple cameras uncompressed from one unit to another to perform analytical operations on them. I think they manged to work at a gigabit, but 10 would be much nicer for them.
What would Joe Sixpack do with it? I'm not sure at the moment. Thing is, since we're working within our limitations today it's hard to concieve of whta use it'd be. However, what happens when it becomes commonplace? It does open doors. Imagine if cable companies traded in coax for ethernet. They could easily send uncompressed HDTV. That'd be pretty slick.
good political satire
Typical desktops of the past few years see roughly ~25 megabyte/sec sustained disk throughput (more for SCSI and more recent ATA models). A switched 1 gigabyte/sec network could easily and transparently support 25 remote drives virtually indistinguishable from local storage.
There are no karma whores, only moderation johns
Just get us the bandwidth - we'll manage to piss it all away. Easy!
1G should be enough for anyone.
-- Nicholas Cravotta, 2004
640K should be enough for anyone.
-- Bill Gates, 1981
I worked for a medical imaging company and they would use it.
they are using gigabit already and you can see slowdown...simply put, a couple hundred 100MB+ x-rays to a single box.... multiply that by however many boxes the hospital has..and 10 gigabit is nice.
The problem hits in not having enough RAM..and with a 4GB limitation on workstation OS's for the most part this amount of bandwidth could get funky.
RoundTop
But just how much data can a person consume?
If I was going under the knife remotely, I'd want the surgeon to have as much bandwidth as possible (and very, very, very low latency).
Tweet, tweet.
That might be just enough bandwidth to get a life-like signal to the holographic projector!
1. When the pin is pulled, Mr. Grenade is no longer your friend.
2. Do not eat iPod shuffle.
"What would Joe Sixpack do with it? I'm not sure at the moment. Thing is, since we're working within our limitations today it's hard to concieve of whta use it'd be."
The Goatse.cx experience in holographic, 5.1 surround-sound, smello-tactile-vision.
OK, so for stuff like streaming MP3s and so forth, this is a little overkill for the current style of usage. However, where I think this will come in useful is for stuff like remote disk and memory access over IP.
:).
With a 10G LAN, you'd be able to come up with a great distributed computer system (e.g. for compiling software). IIRC protocols are in the works now for native-ish memory access over networks, turning a network into one huge computer, and you can already access remote disks with the right software. Imagine the simultaneous distributed encoding of several HDTV streams to redundant archives on several different computers, and you'll probably find that more bandwidth = better.
So yeah, there'll definitely be possibilities for this sort of stuff, even if it is only as a base requirement for the post-Longhorn Windows version
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Seems like this would be useful for people trying to build clusters with commodity hardware.
For distributing intermediate results, I don't imagine there is such a thing as too fast.
While there are certainly applications that don't need to communicate that fast, more bandwidth means more alogrithms can become practical.
It's not like you can use it download porn, unless the action is happening in the next room. This is not a WAN technology.
So, we used to have little dumb terminals that talked to the big smart backend. Then computer became cheaper and we had Personal Computers, but we have to manage and distribute all these updates and it's a real pain and it sometimes destroys your computer during the upgrade/install process. Now we can swing the pendulum back towards the Network Computer a little more.
This isn't a new idea. Software companies like MS would love to sell you a subscription to MS Office which you renew and they in turn patch and maintain the software on your company's server or on the MS servers. It's a neat idea for sure. Companies like Novel have made some interesting claims about Network Computers.
There is also the whole Plan9 type of mentality too.
Sam
PCI is 33Mhz, not 33 MB/sec. 33 X 32-bit-bus = 133 MB/sec. PCI-X goes up to 133 Mhz and 64-bit, so that's 800 MB/sec.
"Close" applies both in physical distance (I have to count picoseconds for the kind of stuff I do) and in network distance, since every router adds considerably.
For some jobs (backup is a classic) latency is relatively tolerable. However, even for those you have to watch out because one error can cause the whole process to back up for retries. Ten to the minus fifteen BER sounds good until you look at what it can do to your throughput in a long-latency environment.
Lacking <sarcasm> tags,
We use lots of shared drives, remote desktop applications, X traffic, moving core files, database dumps, email with very large attachments (exchange to boot).
:)
We migrated to 100meg, it was like night and day, and we still need more. We finally got 1gig to IT's network, and still to slow to push files with lots of users.
We have a burstable OC192 to our 2nd remote datacenter, OC48/12's to the smaller datacenters. But this is for production networks that need bandwidth, not desktop usage.
Also, my buddy in Japan just told me he got 100Meg DSL, the stuff you can do when bandwidth isn't a concern. Already Internet TV stations popping up there, amazing. Can't wait for this to catch on in the US. I just upgraded to 6M DSL from speakeasy, and its too fast for fileplanet.
Speed kills
You won't actually have to control the orcs, the mere sight of them on your screen will initiate instant lag-death for people with lesser video cards.
Machine9dotNet
100 Megabytes per chromosome
x 23 chromosomes per gamete
x 20 million gametes per ejaculation
Therefore Ms. Lewinsky can consume roughly 46,000,000,000 megabytes
(assuming that there is no overflow to a dress)
How much can you consume?
As a CCIE, I have been designing networks for years. I have analyzed traffic to/from desktops and watched traffic to the average desktop never even get above 27mbps. This is due to the average file size of the transfer which is rarely above 10 megabytes. At 10 megs, it only takes a few seconds to get it transfered and it only has a few seconds to get up to speed, by the time it gets all revved up, the file transfer is complete.
High-end workstations such as CAD with gigabit connections, working with 500 mb files, or multi-gigabit video files will occasionally reach 500 to 600 mbps, and even then only for a couple of seconds. At these speeds, power users can use that network connection as if it were a local drive, because at those speeds you are matching the speed at which you're reading/writing data to your local hard drive.
The only time I've ever seen near gigabit traffic at a steady pace was at network servers, where traffic can reach a steady 600mbps on a single gig link - which is maxing out the speed at which the server drive can read/write data to its hard drive. Think of it this way, a 1 gigaBIT link can transfer a 1 gigaBYTE file in about 10 seconds, that's FAST! Conversely, it takes nearly 20-30 seconds just to write that large a file to the hard drive.
Now, on a Cisco 6500 core switch, or a Cisco GSR 12000 where traffic is aggregated, these are the only places where I've actually seen multi-gigabit traffic rates, and that was across the switch fabric - not all directed to a single interface.
The 12000 GSR already has a 10gb interface, it is a single line card that takes up a full slot. It sells for about $60,000 and is used to move data from the switch fabric of one GSR to another GSR, which means you need to put in 2 of them at a mere $120,000 to get the two connected.
Moving to optical links, you can get up to 36Gbps using Dense Wavelength Division Multiplexing on multimode fiber. This uses several colors of laser light to transmit multiple 'channels' across a single fiber link.
Even at these tremendous speeds, they are only used at traffic aggregation points, again because any network device, even a turbocharged SAN couldn't handle reading/writing at those speeds for anything longer than a quick burst.
I say this: If you think that 10gig/sec is your answer, you're looking at the wrong problem. You can get the performance you need at gigabit rates.
I'm not saying that we'll never need 10gigabit to the desktop, just not until we solve the hard drive bottleneck. Solid state storage could solve the problem, but we'd need to have solid state drives that store 100gb of data in order to match the throughput of the network.
Good security is based upon reality and common sense. Common sense is a function of having common knowledge.
Dude, what *is* it with the porn meme? There's like 15 comments to that effect already in this thread, before it broke 50 comments. If every slashdotter was as dedicated/addicted to downloading pr0n as is stereotype goes, the whole freakin' internet would have been DDOSd long ago.
Yeah, I know it's popular, but geez. Not all of us are spending our time gazing and wanking. Some of us actually code (and even talk to women!)
I hereby banish this to the Beowulf cluster of memes, along with Soviet Russia/Hot Grits/Profit!
Libertarianism is rich wolves and poor sheep playing gambler's ruin for dinner.
Well.. ;)
I wish my compu had less ram... so that a system dump takes a bit shorter..
No, thanks :-)
IDE over IP. Yes, it does exist.
It had to be said.
It was.
your harddrive is too slow ;p
Had some pretty slick security cams installed in them from the beginning (~3-4 years ago) - but they couldn't use them. Why? Not enough bandwidth to send the images uncompressed. Which was what they had set them up to do. Solution? Turn off cameras. Wait a few years for more funding.
I think it's you who is the naive child.
Porn continues to be one of the leading drivers of technology (war being the other one) having "made" the VCR, VideoCD, color-printing, Video Streaming, and many other industries.
Porn also continues to be a serious business, with the New York Times (may 18 cover story) claiming Pornography has $10 - $14 billion in annual sales - bigger than any major sports league.
The porn industry employes 12,000 people in California alone, contributing $36 million in taxes to the state. Comcast makes $50 million per year on cable programming. DirecTV is estimated (by CBS) to make $500 million/year.
Recent estimates of Internet porn are that it's about a 1 billion dollar industry.
CBS reports that "Consumer demand is so strong that it has seduced some of America's biggest brand names, and companies like General Motors, Marriott and Time Warner are now making millions selling erotica to America. Correspondent Steve Kroft reports.".
The CBS article claims that Hilton, Marriot, Hyatt, Sheraton and Holiday Inn all offer pay-per-view porn and such programming is purchased by 50 percent(!!!) of guests accounting for 70% of in-room-profits.
" Sorry, it isn't funny, intelligent, and I think most readers would say that you are simply embarassing yourself"
We're not laughing it it -- we're respecting it as an important technology driver, and serious business that is very important to both broadband communication (this article) and other technologies including digital video, alternative payment mechanisms (phone-sex is the biggest driver for phone-calling-cards), etc.
Perhaps one day when you reach puberty you'll understand too.
Ya know, so far everyone seems to think of this as a long distance pipe. It's not, it ethernet. RTFA useful distance is in meters *NOT* kilometers. This is an intraoffice connection not a WAN pipe.
Several hundred megabyte patches.
Oh.
(In other words... true, 10Gb per second isn't available from New York to Hong Kong today... but in 2014, that'll be standard... if not so-three-years-ago.)
Have you been touched by his noodly appendage?
Seriously gentleman, move beyond the teenage years and enter into a discussion that isn't focused around the act of parading women. Sorry, it isn't funny, intelligent, and I think most readers would say that you are simply embarassing yourself.
;)
You must be new here.
Speaking as a heterosexual female in a committed relationship, even I enjoy watching pornography every once in a while. It's not a terrible thing. Besides, after you hang around male geeks for a while, you'll realize that many of them are seriously sexually deprived. Porn is all they have, which is really sad, actually. Makes me want to clone myself to satisfy the male geek population.
Answer: because laypeople insist on talking in imprecise terms like kilobytes and whatnot. Even the byte, historically, could be of varied size depending on the architecture.
When talking about bandwidth, always use bits, and always use k=1000.
Further, how much useful data transfer you get out of the system is not an accurate number.. it fluctuates based on a number of factors, including the network itself, quality of equipment, protocol stack and version, stack settings, local hardware speeds, etc.
However, what we DO know is that the medium transfers *exactly* 10 billion bits per second, no more, no less.
Transmission speeds are measured atthe base rate they transmit data at, without taking into account the protocol in use generally. It has to be this way, because everything else varies upon use. 11Mbps wifi in no way lets you transmit 11mbps of useful data, or anywhere near that, between two hosts.. but the data rate on air is precisely 11Mbps.
A fully utilized 100Mbps ethernet hub will have exactly 100 million bits per second going through it.. yet it is impossible for a single host to transmit at 100mbps continuously.. there are mandatory pauses in between frames, and stuff like that.
Further to that.. to add any kind of meaning whatsoever to download limits, if it's a service you pay for, you need to inquire to precisely how such things are calculated.
This much bandwidth isn't going to help you do any of these things. I upgraded my network to gigabit ethernet about a year ago (from 100 mbit), and much to my surprise, the speed increase was only about 3 times when copying files from one machine to another. I did a little math, and found the answer. Your average ATA hard drive, even at max bus speed, only delivers 0.8 Gbps. And in the real world, you are lucky to get half that from a single drive. In my own test transfers from RAID1 and RAID5 arrays, my transfer rates never once exceeded 0.70 Gbps. Until there is a fundamental increase in the amount of data you can get off a spinning disc, its not likely that a home user is going to saturate a 1 Gbps line, much less a 10 Gbps line.
Let's see. There are about a million pixels on my screen (1280 x 800). Assume 24 bit color, so that's 24 megabits per frame.
... lots of things could be externalized and generalized. This would also allow more devices to be shared across networks more easily, since they're *on* the network in any case. With the Internet, nobody cares about the physical location of the machines they access; likewise, with this system peripherals aren't associated as strongly with one specific computer.
This at 60 fps will be 1.44 Gbps.
So 10-Gbps ethernet is enough to stream the output of a monitor, *uncompressed*, at full framerate, to either a dumb terminal or another computer. Even the most elementary compression (only reporting changed pixels, or PNG/jpeg techniques) could cut this to a fraction of 1.44Gbps.
More generally, it could allow more of the things that are currently on the PCI/USB bus to become external, and could become a more flexible replacement for USB. Scanners, cd writers, audio devices, you name it
This sort of thing might also have applications for cluster computing, allowing more sorts of things to be done with clusters since you have higher inter-node bandwidth.
Actually it's 1064MB/sec...
Double the bus width from 32 to 64 bits and you double from 133MB/sec to 266MB/sec
Now 4x the Mhz from 33 to 133.. 266 * 4 = 1064MB/sec.
maybe so, but you don't work with all your data on the hard drive. Working with data on another computer can really speed up with faster ethernet, especially databases that stay partially in RAM.
Always going forward, 'cause we can't find reverse.
I'm still waiting for decent DSL, since I'm
on 30 year old buried POTS wiring that's 5
(plus) miles away. Fiber to terminal point
will not happen here before hell freezes over,
since the Baby Bells are not spending that
kind of money.
However, with that kind of bandwidth to the
internet, I could set up some homebrew web
sites, and telecommute to work, and go back
to (online) school all at the same time.
I hate to be repetitious, but that kind of
infrastructure would allow some really great
collaborative (beowolf?) computing.
HDTV is broadcast at 20mbit, give or take
Downmix - The Artscene News Source!
Today's "ethernet" doesn't have limitations - it is really only referring to a frame format.
The distance limitations were initially related to running ethernet in half duplex mode, due to the requirement for all devices to be able to detect a collision.
Now that ethernet is run in full duplex the distance limitations due to collision detection have gone.
Distance limitations in "ethernet" are now related to physical media the ethernet frame format is carried over at the specified clock rate. In most cases, cost is providing a constraint, in the sense that longer distances can sometimes be achieved over the same media, however the costs to do so rise dramatically, such that the technology might be priced out of the market it is intended for.
For example, from memory, Cisco have been selling a variant of 1Gbps Ethernet for at least four years now called "1000BaseZX". It would reach around 90 000 metres over single mode fiber. From memory though, the GBICs (Gigabit Interface Converters) were $12 000 US each or something like that, and you needed one per end of the link. And that would be really, really, really cheap when compared with the cost of the 90 000 metres of single mode fibre.
I don't know if the article mentions any distances for 10Gbps, at the moment it has been slashdotted to death.
The Internet's nature is peer to peer - 20050301_cs_profs.pdf
I saw some comments here saying Gigabit Ethernet is enough. There's nothing we can do with 10GbE.
;-)
/whatever to access a UNIX fileserver on the other, we'd all be able to rig up a very nifty setup, and use the combined speed of all our harddrives at home.
I beg to differ. Sit tight.
Here's an idea for you geeks that for some reason nobody is busy doing yet.
Quite a few IT people I know run some form of Linux or BSD server at home, doing a variety of stuff from fileserver to firewall to mail/DNS server etc., though on their desktops they run 2K or XP for reasons such as gaming, simplicity, wife, and so forth.
Here's the idea. Pool all your harddrives at home on the Linux/BSD box, configure a software RAID-5, share it using samba and network-boot all the 2K/XP machines at home from this network-attached storage. Using Gig ethernet of course.
What do you get? Every box gets a system drive "Drive C" that can go at 100MBytes/sec. RAID-5 redundancy for all your machines at home. Harddrives, which generate heat and noise are no longer in your computers.
The benefits are enormous.
There's a small con though - you won't be able to drag your computer to a LAN-party (unless you drag the server too
Currently there is a shortage of one element though: Software that can boot Win2K/XP using PXE from a fileserver. Such software exists in the commercial world and is made by a french company called Qualystem, which doesn't sell it in less than 1-server+25-client licenses, which costs a whopping 2750Euro. They show zero interest in smaller clients. A second product, Venturcom BXP, does the same but falls short as it has a dedicated server that only runs on 2K/XP/2K3 - no BSD/Linux with SAMBA for you.
If someone in the open-source community were to pick this glove up and write a small driver that emulates a harddisk for 2K/XP on one side (the kind you throw in for a RAID controller by pressing F6 when installing windows), and uses SMB
We'd also realize that Gigabit Ethernet is not enough, as a cheap 4-modern-ATA-drive RAID5 setup (which effectively streams enough data to store on 3 of them, one of the four being used to store parity info at any given moment) writes at 40MByte/Sec x 3 = 120MByte/Sec, and reads at 60MByte/Sec x 3 = 180MByte/Sec.
The Gigabit Ethernet _will_ pose a bottleneck.
If we add more drives, the bandwidth requirement broadens.
There's also the small issue of the PCI bus, your server must have its ethernet off the PCI bus, like in Intel's 875 chipset, nVidia's nForce 250 or on a PCI-Express card. Otherwise the IDE and GB will choke each other on the too-narrow PCI bus.
Anyway. once people start doing this, 1000BaseT is back to where 100BaseTX has been for 5 years - choking. I say - Bring on 10GbE!
-
I don't understand why everyone is so impressed with that post. Insightful? I'd say thats just common knowledge.
How fast can your processor communicate with your RAM?
How fast can that ram communicate with the HDD?
How fast can your computer connect to the LAN?
How fast can your LAN communicate with the internet?
See what I mean? It's pretty common understanding that the farther you wanna go, the slower things get.
Well, I guess its not that common since you all modded that +5. I am disappointed in all of you. You are not geeks. Go away.
I haven't said that, but a columnist in Byte Magazine in the mid-80s had a rant about this.
He programmed on a Mac, and the compilation took typically 5 to 10 minutes. Enough to get a cup of coffee, check the newspaper and have a quick chat with a cow-orker. Then he got a new Mac, and it compiled the program in a minute or so. No time for coffee, no time for news, no time for smalltalk.
So the new, faster computer was too fast... he had to wait at his desk more with the new computer.
//TheToon
- Connect backbone LAN switches, e.g. two Cisco 6500 machines, each one full of Gigabit links to access/distribution switches.
- High-speed links for ISPs or research networks. 10GE can reach about 70 km without repeaters and is significantly cheaper than OC-192.
- Link between access and core switches. Since more and more offices are (for some reason) switching to Gigabit to the desktop, the access switches need much bandwidth to deal with the (possible) traffic. A good example is the new Cisco 3750 stackable with 16 GE and one 10GE links.
10GE to the desktop is at this time ridiculous, but don't think that means that 10GE technology is not used.Try to find a host OS with a TCP/IP stack that can properly utilize 1 gigabit ethernet, let alone 10 gigabits. Hint: It ain't Linux...
Try to find a storage solution that can read or write that fast. I'm thinking something like EMC with about 6-8 2 gigabit HBAs using Veritas DMP (dynamic multi-pathing).
Try to get all of the above, along with a 133 mhz. 64-bit PCI-X bus that still can't actually keep up with 10 gigabits of data. (133 mhz. 64-bit PCI-X is only about 1024 megabytes per second, not counting overhead).
The problem is, right now, the rest of the parts of a system just can't keep up with 10 gigabit ethernet. The only box that I would use that can handle that many I/O paths to storage (we're talking six to eight 64-bit 66 mhz. 2 gigabit FC host adapters) is a Sun Fire 6800 or something larger. The problem is, Sun doesn't yet support PCI-X, so now your 10 gig ethernet card is going to be limited to a 66 mhz. 64-bit PCI version, which will only transfer a maximum of 512 MB per second, not counting overhead. That is less than half of the available bandwidth of 10 Gig Ethernet.
You can forget about putting it in any Intel based system. There are not enough I/O busses and I/O controllers in even the beefiest Xeons or Opterons that can handle this much bandwidth (to disk).
Also, if your application doesn't need to write all of that data to disk, then how large is this dataset in memory that needs to be transferred at 10 gigabit speeds? If you had a server with 64 GB of memory, it could transfer it's entire memory set over 10 gigabit ethernet in less than 60 seconds.
A far better, and more economical solution, if you really need 10 gigabits of data throughput to the network, would be to use the same Sun server, and a product called Sun Trunking, which allows you to bond multiple gigabit ethernet interfaces together. You get all of the throughput you want, plus more fault tolerance. I've set it up before, and you can have a continuous ping going, across 4 connections, and pull 3 of those 4 connections and the ping keeps going, without even a dropped packet. It's really fault tolerant, and uses your existing switches, NICs, and hardware, without forcing you to upgrade your entire core switch architecture.
"When the president does it, that means it's not illegal." - Richard M. Nixon
And thats just the tip of the iceberg. Back when the 300bps modem came out they figured the speed was as fast as anyone needed because it was near impossible for anyone to type more then 30 characters per second. Then the 1200 and 2400 bps modem cam out and they though those were as fast as anyone needed because almost no one can read at that rate. Then the 9200 and 14.4k because it takes almost no time to go to the next page 80x25 of colored text. then the 33.6k and 56k modems (Still the fastest modems for 1 normal telephone line) you can now download a 300x200x256 colors picture in no time. As bandwidth increases we find new ways to max it out and also with increased bandwidth we come with new methods of using the computer because it can now do it.
If something is so important that you feel the need to post it on the internet... It probably isn't that important.
"Cardinality" is the number of elements in a given mathematical set. When modems ran at 300 baud, you could forget about sending large data sets, such as images, because text and voice data took up all the available bandwidth. As connection rates increased, so did the cardinality of data that users could send. [...] Video currently represents the highest cardinality data
The term "cardinality" is wrong for several reasons. First, image data isn't represented as sets, it's represented as ordered sequences, and when talking about ordered sequences, both computer scientists and mathematicians talk about their "length", not their "cardinality".
Furthermore, what matters is not the size of what you want to transmit, but the rate at which you need to transmit it. We call that the "data rate" or (somewhat sloppily) the "required bandwidth".
So, the overall point of the article, that there is no single media stream that requires 10 Gbit bandwidth, is correct. However, that's pretty much irrelevant: file servers, video servers, and aggregate usage still require that kind of bandwidth. A family of four might require that bandwidth. You might want that bandwidth to have your backup happen in 1 minute instead of 10 minutes. So, there are lots of reasons to want 10 Gbit Ethernet, provided the price is right.
As for his use of the term "cardinality", the author apparently doesn't quite know the terminology of the field.
Define "properly". If you mean efficiency, that's desirable but not critical. If an Intel/Linux server is 75% the efficiency of a Sun server, yet costs 30% the price, you can install two or three for the same bucks. That's efficiency of a sort too, yes?
Try to find a storage solution that can read or write that fast.
Well, in terms of raw sustained bandwidth, this doesn't seem all that difficult. A single Ultra320 SCSI HBA manages about 2.5 Gb/s, and 4-6 of those should meet requirements. Modern drives can sustain 400-650 Mb/s easily enough, 32 or even 24 of them would give plenty of headroom. 4 per HBA would be ideal. Even consumer 4-way SATA RAIDs would likely do the trick - being point-to-point they have more headroom than a shared SCSI bus (though less transfer efficiency).
Try to get all of the above, along with a 133 mhz. 64-bit PCI-X bus
Thanks, I'd rather use PCI Express. A 4x PCIe slot easily matches PCI-X, but it's point-to-point rather than shared, so I get that much bandwidth for each HBA. Motherboards are in production now with 4x, 8x and 16x slots, chipsets with 32 available PCIe lanes - that's around 80 Gb/s total bandwidth. A dual Opteron system today also has around 80 Gb/s memory bandwidth, and quad- and 8-way systems have much more.
Sun systems have traditionally been right up there with sgi for high-bandwidth servers while humble x86 consumer systems haven't held a candle to them. But that ole' world, it just keeps on changing...
Why would anyone engrave "Elbereth"?
umm. you are kind of correct. two scenarios:
1. A stream of data being pumped via UDP over a WAN which has a satellite link bang in the middle of it. Very high latency i.e. the bits take >600ms to get to the other end, but data can be sent at "wire speed" as there is no acknowledgement of each packet required == potentially massive bandwidth.
2. A large file being FTPed over the same WAN link. FTP typically runs over TCP/IP. TCP requires acknowledgement of each packet being sent. TCP (wrongly) interprets the long Round Trip Time i.e. >1200ms as link congestion and lowers the transmission rate. Oops !
$ strings FTP.EXE | grep Copyright
@(#) Copyright (c) 1983 The Regents of the University of California.
Our plan for 10GbE is to support researchers with huge datasets (in the terabytes) who use our supercomputing facility. We currently use GbE, which is not sufficient for transfering such large amounts of data. So we are upgrading to 10GbE and also getting WAN connectivity at that rate (not sure if this is going to be 10-GigE-WAN-PHY or not) so that researchers across the country can transfer their data in a matter of minutes or hours, as opposed to days or weeks.
For those posters who are complaining about not getting near GbE performance, you are not properly tuning your system and network. You need think big - large frame sizes (network, 9k - 64k), large TCP windows (system buffers - think MB for GbE and GB for 10GbE), large I/O read/write(system disk), and account for latency (calculate your bandwidth*delay product). I've gotten constant ~980 Mbps throughput on a GbE network that was tuned.