Please create an account to participate in the Slashdot moderation system

 



Forgot your password?
typodupeerror
×
Science

8.6 GB Internet? 382

prostoalex writes "Caltech computer scientists announced the protocol, capable of delivering 8,609 Mbps over the Internet, using 10 simultaneous flows of data. The research project was conducted in partnership with CERN, DataTAG, StarLight, Cisco, and Level 3. The practical applications, according to the press release, is ability 'to download a full-length DVD movie in less than five seconds'. There is a number of papers and scientific publications available."
This discussion has been archived. No new comments can be posted.

8.6 GB Internet?

Comments Filter:
  • Nothing new (Score:4, Informative)

    by Billly Gates ( 198444 ) on Saturday March 22, 2003 @07:51PM (#5576040) Journal
    Fiber optics have been capable of delivering up to 200/gb a second in demonstrations for the last 15 years.

    Its just that optical routing is expensive and so would the switch at such a high speed.

  • Re:Argh! 8Gb (Score:5, Informative)

    by XaXXon ( 202882 ) <xaxxon&gmail,com> on Saturday March 22, 2003 @07:52PM (#5576045) Homepage
    Yes, as the original poster said, it's 8.6 giga-BITS per second. Little 'b' means bits, big 'B' means bytes.

    Saying 8.6GB is off by an order of magnitude.

    Sigh..
  • Bloody repeats (Score:4, Informative)

    by blamanj ( 253811 ) on Saturday March 22, 2003 @08:03PM (#5576109)
    Ahem, this was reported here [slashdot.org] a couple weeks ago.
  • by rmohr02 ( 208447 ) <mohr.42@osu. e d u> on Saturday March 22, 2003 @08:05PM (#5576113)
    On the internet, a byte is normally 10 bits--8 bits of data, one starting bit, and one ending bit. Thus, 10Mbps = 1 MBps.
  • RAID (Score:2, Informative)

    by yerricde ( 125198 ) on Saturday March 22, 2003 @08:08PM (#5576140) Homepage Journal

    Not only can a high-end storage array handle that sort of throughput, but it can do it without any bugs [bugfreeliving.com].

  • Re:Argh! 8Gb (Score:5, Informative)

    by addaon ( 41825 ) <addaon+slashdot.gmail@com> on Saturday March 22, 2003 @08:10PM (#5576156)
    More nitpicking, yay! (a) If we assume base 10, it's actually ~0.9031 (log[10](8)) orders of magnitude off, as this is a logarithmic measure; (b) why are we assuming base 10? Base 2, which makes a lot more sense for this thing, gives us an even three orders of magnitude off; as a comment below mentioned, octal gives exactly one.
  • Re:Nothing new (Score:5, Informative)

    by Lothsahn ( 221388 ) <Lothsahn@@@SPAM_ ... tardsgooglmailcm> on Saturday March 22, 2003 @08:12PM (#5576169)
    Sure, we can deliver 200 gb/sec in fiber optics.

    This isn't talking about delivering raw speed over a point to point connection but delivering a large amount of data over a shared network. It's talking about a protocol rather than a transport medium, which must account for problems such as error, latency, bandwidth, and flow control.

  • Overhead (Score:5, Informative)

    by yerricde ( 125198 ) on Saturday March 22, 2003 @08:13PM (#5576179) Homepage Journal

    It is just over a gig a second.

    Not all of that is data. Some is packet headers. Some is error correction. That's why you can't push 6 KB per second over a v.90 dial-up connection at 48 kbps.

  • by cperciva ( 102828 ) on Saturday March 22, 2003 @08:16PM (#5576189) Homepage
    IP can scale, yes, but TCP (as originally designed) can't scale very well. It severely breaks under multipath routing, and tiny rates of packet loss can dramatically limit throughput, for a start.
  • Re:Eight giga-whats? (Score:1, Informative)

    by Anonymous Coward on Saturday March 22, 2003 @08:57PM (#5576364)
    Okay, let's see:
    Spam emails in my Hotmail account run (on average) 7 kiloBYTES, or 56 kilobits. Now if this connection will give you 6,609 megabits, that's 8,609,000 (roughly) kilobits per second. That's 153,732 spam messages per second. Times 86,400 seconds per day, that comes to 743,817,600,000 - 743 BILLION spam e-mails per day. Of course, that would come to almost 5 terabytes (not -bits) per day, so your disks would, as other posters have mentioned, be the lowest common denominator.

    Just FYI.
  • Re:Argh! 8Gb (Score:3, Informative)

    by damien_kane ( 519267 ) on Saturday March 22, 2003 @09:09PM (#5576397)
    (4.7G on a SSSD (single sided, single density - not that anybody remembers those)

    Actually when talking about DVDs, the density of each layer cannot change.
    I believe you are referring to SSSL (Single-Sided, Single-Layer) DVDs, as each since on a regular red-ray DVD disc can have two layers of data.

    I'm not sure if that's the same for the famed blu-ray discs or not, I would appreciate it if someone could enlighten me.
  • Re:Bottleneck (Score:5, Informative)

    by Emil S Hansen ( 143865 ) on Saturday March 22, 2003 @09:19PM (#5576428) Homepage Journal
    Assumin its actually 8.6 bytes/sec and not bits like another poster suggested, the pci bus would become oversaturated since it can only transfer 3.2 gb/sec ( correct me if the transfer rate is wrong).

    A 33 MHz/32 bit PCI bus which is standard in most PCs will transfer 133 MB/sec.
    A 66 MHz/32 bit PCI bus which is in quite a few Intel and UNIX servers will transfer 266 MB/sec.
    A 66 MHz/64 bit PCI bus which also is quite common in UNIX servers (and becomming in Intel) will transfer 532 MB/sec.
    A 133 MHz/64 bit PCI bus which is the current standard for big UNIX servers will transfer, you guessed it, 1 GB/sec.
    Mind you that these numbers are pr. PCI bus, some of the lager Intel servers, and most UNIX servers have more than one PCI bus.

  • Re:Argh! 8Gb (Score:3, Informative)

    by Anonymous Coward on Saturday March 22, 2003 @09:28PM (#5576460)
    Because the phrase order of magnitude is by definition a factor of ten.

    Look it up: Dictionary.com definition of order of magnitude [reference.com]

  • Um. . .Actually it's (Score:1, Informative)

    by Anonymous Coward on Saturday March 22, 2003 @09:29PM (#5576465)
    Marge: "Does anyone need that much porno?"
  • Re:Nothing new (Score:5, Informative)

    by Anonymous Coward on Saturday March 22, 2003 @09:54PM (#5576546)

    If you read the article, you'll notice that they're talking about a new transport protocol, not a physical layer. Yes, physical layers have been able to run faster than 8 gig for quite a number of years. But if you run a TCP session across such a link, the window sizes, congestion control algorithms, ack timers, and such features keep you from getting anything like the speed of your physical link.

    To illustrate with a point from the article, TCP over the 1 Gbps link they were apparently using typically maintained a throughput of about 270 Mbps, only 27% efficient even when that one session had the whole link to itself.

    Previously, no one much cared, because you used those multi-gigabit links by multiplexing a whole bunch of different users; each user saw a much slower link. So, the old, slow TCP was adequate. (To a point, of course; people have noticed problems with TCP acks even on DSL links.)

    One of the purposes of the "Internet 2" research and other projects was to develop protocols that would allow _single connections_ to run at very high speeds.

    The announced protocol, according to the article, managed 95% efficiency and 925 Mbps with a single flow, and 88% efficiency and the 8.6 Gbps of the headline with 10 concurrent sessions over a 10 Gbps link.

    So, yes, it is something new.

  • Re:Argh! 8Gb (Score:3, Informative)

    by slittle ( 4150 ) on Saturday March 22, 2003 @10:00PM (#5576581) Homepage
    Depending on your communications medium, it's probably 10 bits per byte, not 8. And it's just easier for us humans to pretend it's 10 regardless.

    Base 2 is pointless because comms people use SI prefixes properly*. 1 megabit = 1,000,000 bits. Base 10.

    *Probably because not all platforms use 8 bit bytes (encoded to 10 bit bytes for transmission). The comms mfr's only care about the rate on the line.
  • Re:CalTech (Score:5, Informative)

    by ccnull ( 607939 ) <null@filmcriWELTYtic.com minus author> on Saturday March 22, 2003 @10:02PM (#5576590) Homepage
    10Gbps Ethernet already exists [itworld.com].

    The problem is that the fastest hard drives on the market today are Ultra320 SCSI, which have a throughput of 320MB per sec... or about 2.5Gbps. Even that's theoretical, of course. And few people have an all Ultra320 datacenter.

    Just pointing out that the cabling is hardly the bottleneck when you reach that kind of speed, even at the LAN level. I've seen so many people upgrade their switches to gigabit ethernet then scratch their heads wondering why the network is still slow... when the server in the closet hasn't been upgraded in 5 years. Storage will continue to be the bottleneck on the LAN for a long time to come.
  • Re:Nothing new (Score:5, Informative)

    by SiliconEntity ( 448450 ) on Saturday March 22, 2003 @10:03PM (#5576595)
    No, this really is new! It is over the regular Internet, a connection from California to Switzerland, that they achieved 8 Mbps:
    Using standard packet size that is supported throughout today's networks, the current TCP typically achieves an average throughput of 266 Mbps, averaged over an hour, with a single TCP/IP flow between Sunnyvale near SLAC and CERN in Geneva, over a distance of 10,037 kilometers. This represents an efficiency of just 27 percent. The FAST TCP sustained an average throughput of 925 Mbps and an efficiency of 95 percent, a 3.5-times improvement, under the same experimental condition. With 10 concurrent TCP/IP flows, FAST achieved an unprecedented speed of 8,609 Mbps, at 88 percent efficiency, that is 153,000 times that of today's modem and close to 6,000 times that of the common standard for ADSL (Asymmetric Digital Subscriber Line) connections.

    They achieved this by modifying the TCP protocol to be more efficient. It's a huge improvement.

    Of course you'd need a big pipe to the net to be able to handle this bandwidth; it will be quite a while before home users could see this kind of speed. But the new protocol sounds like a big win over regular TCP and hopefully it can be rolled out relatively quickly.

  • by Loualbano2 ( 98133 ) on Sunday March 23, 2003 @12:02AM (#5576934)
    Before everyone gets their panties in a bunch over what Dan said here, let me try to clarify what he means by unreliable.

    Unreliable in this context does not mean you can't depend on it, it means that it is an 'open ended' protocol other wise known as 'best effort' which means there is no delivery confirmation at that level of the OSI model. Basically when an IP packet or an ethernet frame goes out on the wire, that device has no idea whether it got where it was supposed to go. Think about regular postal mail vs. a registered letter.

    As mentioned, those protocols rely on higher (higher as in the OSI model) level protocols to do error correction/detection and retransmission requests, such as TCP.

    -ft
  • Re:CalTech (Score:5, Informative)

    by Sycraft-fu ( 314770 ) on Sunday March 23, 2003 @03:34AM (#5577466)
    Just a note that the bottleneck of drives isn't a problem at this point since for now 10Gb ethernet isn't targeted at the desktop or server. It is for links between switches. If you have a switch loaded full of Gb connections, you'll probably want something mroe than just a Gb connecting it to its neighbours. However going to ATM or POS really isn't great since you then have to route instead of just switch. Enter 10Gb ethernet to solve the problem.
  • by zatz ( 37585 ) on Sunday March 23, 2003 @04:43AM (#5577585) Homepage
    This is useless to the Pentagon. Their problem is a shortage of raw bandwidth, not lack of a transport which can efficiently use what is available.
  • by Anonymous Coward on Sunday March 23, 2003 @05:32AM (#5577664)
    A byte is not defined to be 8 bits. A byte is the smallest addressable unit of storage, which on most modern architectures is 8 bits.

    Some older architectures used 7-bit bytes; some had 9-bit bytes.

Happiness is twin floppies.

Working...