Want to read Slashdot from your mobile device? Point it at m.slashdot.org and keep reading!


Forgot your password?
Microsoft The Internet

Microsoft Wants P2P Avalanche to Crush BitTorrent 545

pacopico writes "Microsoft seems to think it can be the better Bittorrent. You know faster and more well-behaved. The Register has a story on the P2P work being done by Microsoft's researchers in the UK. Redmond reckons its "Avalanche" technology will be 20 to 30 percent faster than BitTorrent. It's meant for legal downloads only, of course."
This discussion has been archived. No new comments can be posted.

Microsoft Wants P2P Avalanche to Crush BitTorrent

Comments Filter:
  • by Anonymous Coward on Thursday June 16, 2005 @04:06PM (#12835203)
    It's meant for legal downloads only, of course.
    Well BitTorrent is meant for legal downloads too, but that doesn't mean a whole lot.
    Naturally, Microsoft is very keen to stress that this technology should be used for distributing legitimate content. It even put that in italics in the press material.
    Oh, never mind, I didn't realize they put it in ITALICS, that is sure to stop piracy dead in it's tracks.

    Besides BitTorrent might not be the most efficient P2P system any more, but it is one of the most widely used. I guess this is what Microsoft does best, copy other technology, add a little to it, then destroy it.
    • by Rei ( 128717 ) on Thursday June 16, 2005 @04:12PM (#12835308) Homepage
      On the contrary, I think it will not destroy it but legitimize it. Now people can say "Even Microsoft is developing P2P!". Plus, with a big backer like MS behind it, we might start to see pressure for more incorporation of P2P into other arenas - for example, a smoother mix between P2P content serving and conventional web serving, with seamless browser support. Microsoft loves tie-ins, after all, even if the products that they tie together are inferior to other products on the market.
      • by robertjw ( 728654 ) on Thursday June 16, 2005 @04:28PM (#12835505) Homepage
        Plus, how cool is it going to be to download Windows Server 2006 (or whatever it is) off a P2P network they created.
      • I think the grandparent meant destroying BitTorrent, not P2P.
        • by VernonNemitz ( 581327 ) on Thursday June 16, 2005 @05:16PM (#12835950) Journal
          And in this case, by creating a BitTorrent work-alike, they can draw up patent specs that INCLUDE BitTorrent's features, and then use that patent to shut down the servers. Time to start informing the Patent Offices!

          Also, folks, make a note of the DATE of that paper describing Avalanche. One PTO rule that seems to me gets violated often is that there is supposed to be (or used to be) a one-year limit between the public release of an invention's description and the patent application. After more than a year, it's too late to apply. How many existing dubious patents were applied-for too late and could be overturned on those grounds?
      • by ImaLamer ( 260199 ) <john.lamar @ g m ail.com> on Thursday June 16, 2005 @04:35PM (#12835580) Homepage Journal
        "Even Microsoft is developing P2P!"

        Really, their server products already use a P2P or S2S (Server To Server, servers being each other's peers...) technology for domain replication. Windows 2000 is pretty darn good at replicating its content even when the original copy isn't available.

        Of course, YMMV, and the right setup is key.
      • by shadowmatter ( 734276 ) on Thursday June 16, 2005 @04:35PM (#12835581)
        Microsoft Research has been working on efficient, decentralized, and fault-tolerant P2P systems since 2001. See the paper about their DHT (Distributed Hash Table) called Pastry [microsoft.com], which was co-authored with Rice and is still under active development there. Note that the Kademlia DHT, which followed roughly a year later and is now used in a variety of P2P networks (eMule, the new decentralized BitTorrent network, etc.) employs a variant of Pastry's routing algorithm of longest prefix matching.

        They still have quite a presence if you look through recent NSDI [usenix.org] or IPTPS [cornell.edu] conferences. Note that this paper is for IEEE INFOCOM, which is big.

        - shadowmatter
        • MMMMmmmmm....Microsoft Pastry.... /Homer
    • Comment removed (Score:5, Insightful)

      by account_deleted ( 4530225 ) on Thursday June 16, 2005 @04:15PM (#12835344)
      Comment removed based on user account deletion
      • Re:Better? No. (Score:2, Insightful)

        Here's where I call BS: "20-30% faster."

        I don't know. I wouldn't underestimate the MS marketing beast. They've done better before.

        Let's say, they tell their users it will be "faster". Everybody knows MS users are idiots. With the new firewall in SP2, there's no way more than 20% of them know how to open a port for bittorrent anyways. Of that, I'd bet even less are motivated to do it all the time. So, bittorrent is either worthless or slow for 80% of Microsoft users.

        Bam! In comes the Microsoft "so
      • Re:Better? No. (Score:4, Interesting)

        by man_of_mr_e ( 217855 ) on Thursday June 16, 2005 @04:43PM (#12835662)
        Actually, if you read the actual research paper, you can see WHY it's faster. Basically, it combines two technologies. A bittorrent like protocol, and file parity generation (such as PAR). This allows you to generate additional pieces you didn't download and reduce the amount of code you need to download by about 20-30%.

        This also solves "the last block" problem where everyone is waiting for the last block, since if you have 99% of the blocks you can generate what's left.

        It's an interesting approach.
        • Re:Better? No. (Score:3, Informative)

          by StikyPad ( 445176 )
          This also solves "the last block" problem where everyone is waiting for the last block, since if you have 99% of the blocks you can generate what's left.

          Not really, it just (possibly) changes the nature of the last block. .PARs don't require any less data to be downloaded, it's just that you can substitute parity data for the original data, then do whatever transformation on that to get the original data back. If the file you're trying to get it 1GB, you're still going to need to download 1GB, whether it
    • Italics, no. Velvet rope, hell yeah! Nobody ever crosses the frickin' velvet rope. MS Firewall? Forget about it, just give each user a standard issue velvet rope to wrap around their computers and NOBODY will dare break in.

      Adware and spyware? Who needs to buy GIANT when you can buy a velvet rope factory and rid these Internets of vermin forever?

      P2P apps sharing copyrighted material? Velvet rope will keep them from doing that. It's red, it's fuzzy, and it's in their way -- NOBODY crosses the velvet
  • Alright! (Score:4, Informative)

    by qw(name) ( 718245 ) on Thursday June 16, 2005 @04:06PM (#12835206) Journal
    The ultimate in spyware!!!
  • I can't wait to get my legal Slackware images 20-30% faster :-)
  • point? (Score:4, Funny)

    by Anonymous Coward on Thursday June 16, 2005 @04:07PM (#12835215)
    It's meant for legal downloads only, of course.

    Then what's the point?
    • Re:point? (Score:4, Insightful)

      by ray-auch ( 454705 ) on Thursday June 16, 2005 @04:38PM (#12835613)
      How about the fact the current MS windows update is real slow because it is client-server and there are always going to be hundreds of millions of clients all wanting the same damn thing at the same damn time.

      The patches ain't getting smaller either.

      This is exactly the sort of problem BT was built to solve.

      Even if they restrict it to only MS authorised updates it might still be a big win for them and, arguably, Joe windows user.

      On the other hand, if they screw up on whatever verification they put in (and they haven't exactly got a good track record on crypto implementations) then you've got virus heaven...
  • by Phoenixhunter ( 588958 ) on Thursday June 16, 2005 @04:07PM (#12835218)
    Palladium anyone?
  • Question is.. (Score:5, Interesting)

    by wfberg ( 24378 ) on Thursday June 16, 2005 @04:07PM (#12835223)
    Will it block access to MP3 files and a big list of other file-types/filename-extensions? Like MSN Messenger 7 does? But, like MSN Messenger, allow .WMA files? And do this under the guise of "security", alleging that MP3 is an "unsafe" format (though unlike WMAs, MP3s can't launch websites or "acquire licenses" and stuff like that)..
  • Innovate this! (Score:3, Insightful)

    by Seumas ( 6865 ) * on Thursday June 16, 2005 @04:07PM (#12835225)
    By "more well-behaved" they, of course, mean "DRM capable"... Innovation is taking everyone else's great ideas and adding "DRM capable" to the name.

    (Yes, I know there is a bit more to their proposal.)
  • Any versions of Windows that show up on there will either have adware bundled with them or, when installed, will cause blue screens endlessly with the error "AVALANCHED_J00_F00" on them.

    And then there's the whole concept of distributing porn via Avalanche; it gives the term snowball a whole new meaning.
  • by the_skywise ( 189793 ) on Thursday June 16, 2005 @04:09PM (#12835242)
    It's illegal "wink wink nudge nudge" to copy Windows 3.1/98 but it helps spread windows users so that's a good thing.

    It's illegal "wink wink nudge nudge" to use our faster service, but it helps support Microsoft so that's a good thing.

    (It's not a bad idea, if it gets popular enough they can just roll it into Office and charge huge $$$ for it like their MSN Messenger 8...er... Microsoft Virtual Meeting...)
  • by soupdevil ( 587476 ) on Thursday June 16, 2005 @04:09PM (#12835244)
    Sounds familiar. My car is meant for legal speeds only. Which is why the "55" is highlighted in a special color. On my 140mph speedometer.
    • by Simonetta ( 207550 ) on Thursday June 16, 2005 @04:33PM (#12835568)
      I read that in Singapore, the world capital for techo-fascist innovation, trucks would have flashing lights attached to poles on the side of the cab. When a sensor on the engine detected that the truck's speed ever went above 35MPH, the light would start blinking. Then the first police car to see it would issue them a speeding ticket.
      If only half the things that I've heard about Singapore are remotely true, then this is one seriously weird place that reasonable people would be wise to avoid.
  • I guess someone in readman finally read the stories about Kazaa's spyware and said "Hey, we're the kings of viruses and spyware! we need in on this p2p thing!"
  • then no matter how "good" MS makes it then it'll never beat bittorrent.

    In other words, it'll never beat bittorrent.
  • by Ochu ( 877326 ) on Thursday June 16, 2005 @04:09PM (#12835253) Homepage
    So you will find your way to debian_iso.avalanche, download it, and find that it has transformed into a handy little PDF explaining why linux bites...
  • by TedTschopp ( 244839 ) on Thursday June 16, 2005 @04:09PM (#12835257) Homepage
    Spyware is found in Bit Torrent.

    Microsoft Releases competitor to Bit Torrent.

    Wow, I'm so glad they were so responsive to that problem. It only took them a couple of hours! That's amazing!
  • by TripMaster Monkey ( 862126 ) * on Thursday June 16, 2005 @04:10PM (#12835264)
    ...You will be assimilated.

    Microsoft has always been about the assimilation of the technology of other companies...that in itself is no surprise. But between their music subscription service [slashdot.org], their new image editing program [slashdot.org], and now this [theregister.com], they've fired warning shots across the bows of three different types of applications, all in the space of a week and a half.

    Is this just a momentary flurry, or can we expect this escalation to continue?
    • Perhaps they're just trying to create enough of a distraction so that people forget that Longhorn still hasn't shipped.
    • Microsoft sees itself running out of runway. It's hard to grow when your market penetration is as high as theirs is. They basically rely on new computer users to help them grow as convincing old customers to upgrade only maintains their last financial position.

      They have the ability to enter many other markets all at once, so that's what they're doing hoping they'll stick in a few places. Music is an easy one. This P2P app is also easy because they can include it with Longhorn, release their own patches wit
  • by NardofDoom ( 821951 ) on Thursday June 16, 2005 @04:10PM (#12835270)
    Microsoft is developing P2P technology because their bandwidth bill from people downloading patches is threatening their profitability!


  • Maybe this is exactly what we need. Microsoft technology that allows people to steal stuff.

    I'd like to see the RIAA/MPAA sue Microsoft for providing a P2P app.
  • Mh.. Microsoft..
    Will linux-images be declared illegal then, too?
  • Can we stop... (Score:5, Insightful)

    by Anonymous Coward on Thursday June 16, 2005 @04:11PM (#12835291)
    ...the knee-jerk reactions that this story will elicit? The original post really doesn't do TFA justice.

    This is basically an improvement to the BitTorrent protocol that will overcome scheduling difficulties that really do exist today (I need piece X, but the person who has it is busy uploading piece Y).

    What it is NOT:
    1.) A Microsoft-proprietary application (at least nor yet).
    2.) A production application that only runs on Windows.
    3.) In any way (in theory, at least) tied to DRM'ing anything.
    4.) A way for Microsoft to track your downloading.

    Basically, Microsoft has suggested a way to make BitTorrent-like downloads better. Microsoft! Making P2P downloads of large files easier! Really!

    This isn't MS search trying to overtake google, or some such. MS isn't trying to own the P2P market (at least not yet). They're suggesting improvements, and if you read TFA, the improvements make sense.

    This is a Good Thing. Yeah, I'm suprised it came from M$ too.
  • Distributed PAR2 (Score:5, Informative)

    by Ececheira ( 86172 ) on Thursday June 16, 2005 @04:13PM (#12835310)
    The way the Register describes it, it appears that rather than sending out chunks of the actual file, it's sending out something similar to PAR chunks where once you have enough data, you can reconstruct the original file.

    Futher, with a few chunks, you can calculate new chunks to send over to others, that way more people have access to more of pieces of the file.

    Sounds interesting, I wonder if it'll be incorporated into the next version of BT.
    • Okay, I'm no CS major, but don't you have to have the same number of bits regardless of the transfer type (assuming complete compression)? I mean, if I send you 500MB of file and 500MB of PARs to reconstruct the 1GB image, have I really saved any download bandwidth? I thought the whole idea of the PAR2 files was you could get just as many segments as you needed (ie - were corrupted) by proving a 1-2-4-8 type sequnce of par files, not that you could send less information from which the orignal file could be
      • by 1000StonedMonkeys ( 593519 ) on Thursday June 16, 2005 @04:30PM (#12835523)
        Here's the thing. If you have a number of par files and all of the original segments, then there are many more pieces you could potentially download. If you need to download 500 of 500 segments, the number of sources you can download from begins to dwindle as you get on towards 400 or 450 pieces (I'm just making up these numbers, but you get the point). If instead, you need to download 500 of 1500 segments, chances are there won't be a scarcity of segments even at 499.

        IMHO, this is actually a really good idea, since I for one would take the added CPU overhead of processing parity files in return for more sources to download from. I've got spare CPU cycles anyway.
    • Unless I'm mistaken, PAR doesn't reconstruct files out of thin air or some crazy algorithm. Bits from all files being sent are passed around in other files, so with enough other files you can reconstruct a missing file. This is valuable on Usenet binary groups where files are often missing, but is not so valuable for BT where files are authenticated.
    • Re:Distributed PAR2 (Score:4, Informative)

      by MikeBabcock ( 65886 ) <mtb-slashdot@mikebabcock.ca> on Thursday June 16, 2005 @04:33PM (#12835566) Homepage Journal
      Its mathematically impossible to do this with less data than an original already-compressed stream.

      PAR data is additional redundant data to allow reconstruction of files for which not all the original blocks are any longer available.

      This is a *real* problem in some cases, mind you, but it requires sending *more* data, not less.

      The additional data is either padded onto each block (as they describe it) or as additional blocks (the way RAID5 or PAR works). Either way, you're talking about having *more* data on average.

      If no seeds become available *and* all the available peers do not combined have all of the blocks you each need *and* the blocks that are present are sufficient to reconstruct (from their redundant bits) the missing blocks, this becomes useful.
      • Re:Distributed PAR2 (Score:5, Informative)

        by ChadN ( 21033 ) on Thursday June 16, 2005 @05:40PM (#12836200)
        A simple example for those reading who don't understand, then some follow up comments:

        Say I have bits 'a' and 'b', that other people want.

        I could sent bit 'a', then bit 'b' to receiver FOO, who can pass them on to others. However, if I send bit 'a' first, and others want 'b', they have to wait.

        Now, instead of transmitting to FOO bit 'a' then bit 'b', I send to FOO ('a' XOR 'b') first, then either bit 'a' or bit 'b'. I'll end up sending FOO the same amount of information (assuming the order is specified in the protocol itself).

        BUT, and here's the cool part. If someone already has 'a', they can get ('a' XOR 'b') from you, and complete their set of data (bits 'a' and 'b'). Furthermore, if someone already has 'b', they also get ('a' XOR 'b') from you, and complete their set. So, by only downloading 1 bit, instead of 2, you can complete the set for others who already have one or the other bits.

        Now, in practice it'll get a lot more complicated, and the method presented in the paper is not exactly like I describe, but the idea is that you can send data to help people complete their data sets, even though you yourself do not yet have the actual uncomputed data. Instead, you have a computed function of the data, which others can use immediately, and from which you can reconstruct the actual data later when you have more information.

        The practical upshot is that the computed data is more valuable to other peers than the uncomputed data, as they may be able to use it to complete their data set, rather than wait for the remainder of the uncomputed data.

        So, in reference to your comments, it may not be so much more practical to any one receiver; they still need to wait for all the data, in either computed or uncomputed form. But, for the network as a whole, it means that each receiver has many more options from which to download and compute each chunk, and thus make available to others. It is not hard to imagine that this can benefit the overall throughput of the network (which the authors of the paper claim).
    • Re:Distributed PAR2 (Score:4, Informative)

      by Wesley Felter ( 138342 ) <wesley@felter.org> on Thursday June 16, 2005 @04:38PM (#12835621) Homepage
      Bram won't add FEC to BitTorrent because he's not convinced of the benefits in real-world situations. (Like most papers on this subject, Avalanche omits a lot of real-world details.)
  • Why are they so eager to announce this? The MPAA has already said they want to crush P2P, especially BitTorrent, and they'll do it by polluting the download pool with invalid content. With this announcement, MS is just inviting the same from their detractors. And they have far more detractors than BitTorrent has.

    Given their security record, any MS-created P2P application will be just one more gaping hole in their Swiss-cheese-inspired security implementation.
    • This paper is from some researchers who have nothing to do with Microsoft's products. MS may not ever use this technology in any product. And if MS does use Avalanche for something, it will probably be buried away inside some other application (like Windows Update) instead of a standalone app.
  • Hmmmm (Score:3, Insightful)

    by technomancer68 ( 865695 ) on Thursday June 16, 2005 @04:14PM (#12835323)
    The scary thing is that if you are a windows user, what's the stop M$ from requiring any updates and patches to come through this new P2P system, thus making it almost mandatory to install it on your system if you ever want to update your OS. Microsoft doesn't want to compete, they want to force.
    • Re:Hmmmm (Score:3, Insightful)

      by PaxTech ( 103481 )
      The scary thing is that if you are a windows user, what's the stop M$ from requiring any updates and patches to come through this new P2P system, thus making it almost mandatory to install it on your system if you ever want to update your OS. Microsoft doesn't want to compete, they want to force.

      Yeah totally.. Like now they make their patches and updates come down over this newfangled TCP/IP thing.. And you HAVE to install it to get updates!! OMG what is the world coming to?

      Let's get a grip here. It'
  • by chris09876 ( 643289 ) on Thursday June 16, 2005 @04:15PM (#12835333)
    The open source community has really been the driving force behind technolgoies like BitTorrent. Sure, obviously other applications have good legitimate uses for BitTorrent-like technologies too, but the technology-savvy crowd are really the people who are using things like BitTorrent... whether it's for slackware images, or anime episodes :) With a closed-source solution from MS, I'd be shocked if it gained a huge following. The momentum from the tech crowd just wouldn't be there.
  • Same old thing (Score:3, Insightful)

    by Sierpinski ( 266120 ) on Thursday June 16, 2005 @04:16PM (#12835353)
    This reminds me of when Microsoft wanted to crush MP3, and came out with a highly proprietary format that nobody wanted to use for many reasons, one of which being the ability for the software to curb the usage of copyrighted media. I'm not advocating piracy, but if you're already using a tool that does what you want, and is free, and is... (did I mention it was free?) why switch?

    Why should users be expected to dump their already-in-place tools and formats for a probably-proprietary version made by microsoft? Its no secret that MS wants to make money, so if you have a choice of a relatively stable and free version, or a new version by microsoft, which would you pick?

    • Okay, let's carry this a little further. What eventually happened to that highly proprietary format that nobody wanted to use?

      Looks to me like it's the de-facto method of internet video distribution. It'll probably be part of the new DVD standard. It's pretty much crushed competing media players on the most popular desktop OS in the world. The EU forced MS to unbundle it, but no one wants the unbundled version because there is no alternative. When MS gets around to integrating it into cell phones, it'
      • Re:Same old thing (Score:3, Insightful)

        by m50d ( 797211 )
        I think he's talking about the _audio_ format, wma. Wmv succeeds because it's actually a very good codec for low bitrates. I have a wmv music video that is smaller than an mp3 of the same song. Wma, as far as I can tell, hasn't gone anywhere. (Lots of music stores selling it, and players playing it, but at the moment apple ownzors them)
  • Bram Cohen! (Score:3, Funny)

    by sinserve ( 455889 ) on Thursday June 16, 2005 @04:17PM (#12835359)
    You made it man, you fucking lucky sunnofabitch. Microsoft wants to compete with your work, that's a badge of honor man, you're made now.

  • It's meant for legal downloads only, of course.

    I wonder how long it'll take to seed my Win2Ksrc.zip file.

  • The nice thing about this technology that it will only be available for Windows. Then again, Apple could create a similar application and call it Tsunami. Gotta love these names.
  • "It's meant for legal downloads only, of course."

    I'm trying to think if there is anything "Legal" I want to download.

  • "Hey guys, I got a great idea!"
    "What's that, Bill?"
    "Well, I've been downloading copies of Napoleon Dynamite off of this site called Suprnova.org using this awesome new technology called Bittorrent!"
    "What does it do?"
    "Well, guys, you won't believe it: It decentralizes the process completely -- no ugly middleman file-sharing program to get in the way! Think we can harness it?"

    ... six months later...

    "Well, Bill, here we go, we created this technology called Avalanche, it's just like WMA! 30% better and

  • The lead-time required to "authorize" any file I want to put up (how are they going to circumvent basic encrypted files named .jpg?) will nullify any technical advances that will make it 10%+ faster much less 20 or 30 over the same network, namely the internet at large.

    Why would I use this again?
    Oh yeah, MAYBE POSSIBLY because small underused networks are sometimes easier to search or seed. Avalanche should fit this model nicely since the developers at MS haven't come up with any earth-shatteringly ingenio
  • that these fuckers won't get into? okay, video game comsoles. lotsa money there. P2P? how are they going to make a dime? competition is great, but they seem to do things just to do them, when other established technologies, protocols, or systems are in place. and it isn't to enter a market, it's to destroy a market. yeah, i know why they do it, but it is amazing really.
  • The best way for Microsoft to stop distribution of pirate warez versions of their software is to control the software distibution network.

    The best way for Microsoft to keep Google from inovating in yet another area is to get there first.


  • I gotta say they come up with some nicer names for stuff than many open source projects out there.

    BitTorrent vs Avalance.

  • This is an academic research paper, and one of the authors in in MS Research UK. He gets paid to come up with researchy ideas, not to build products or do anything related to MS's business. No P2P product will ever be release by MS based on this technology. Why in the world would they want to make a ton of enemies without making any money?
  • Microsoft Research's approach gets around this by re-encoding all the pieces, so that each one that is shared is actually a linear combination of all the pieces, fed into a particular function. The blocks are then distributed with a tag that describes the parameters it contains.

    So, essentially what they're doing is bundling in a PAR like system. This will add quite a bit of overhead as you need to "recover" the entire file using the PAR files, rather than just copying them into the correct spot. I don't

  • pirated versions of MS Office became the most popular shared files.
  • TFA does not make any reference to competing with Bittorrent, nor does it indicate that m$ will be releasing their own P2P client. TFA does link to a white paper [microsoft.com] in which the researchers discuss how they solved the following problem:

    towards the end of a download, any one downloader could have a while to wait for the particular pieces he needs. As the number of receivers increases, scheduling traffic also becomes more complex, and the whole process slows down.

    Nothing particularly evil about that. No m

  • In other news, Microsoft announces that they believe they can do everything better. Whether it's copulation, corpulence, cognitive dissonance, making cars, driving cars, smashing cars, going into space, falling down, drinking, smoking odd chemicals, giving birth, open heart surgery, baking cakes, frying eggs, urinating, indigestion, folding napkins, digging holes, filling holes, etc., Microsoft has announced that they intend to do it all. There's nothing that Microsoft can't do, and won't do. Soon Micros
  • Before people jump up and down on the "legal only" comment, go read the white paper linked in the article. It's actually got some interesting ideas, and (from what I've skimmed through so far) doesn't state anything about dealing with "legal" versus "illegal" downloads - it even mentions Bittorrent favorably in its use to retrieve Linux distributions. The writers just want to tweak out some weaknesses - something I noticed the other day when I was at 99.9% of a recent Bittorrent download, and that 1% had
  • In a recent talk at Stanford Bram Cohen recent commented on people trying to be "clever" in his words. The fact of the matter is that Bram's protocol works because it assumes that every client is out for it's own best interest. The moment you start adding features that require a client give "truethful" information concerning order of packets or whatsoever you open the door for people cheating and trying to leach more than give. MS's idea is just another "clever" idea which forgets this.
  • P2P downloads YOU!
  • Okay, I read the horrible Register article (I can't stand that site) and followed their link to the original pdf [microsoft.com] from Microsoft. (The press release mentioned by the Register was not linked to.)

    In the pdf, they explain on page 10:
    The main advantage of using network coding for distributing
    large files is that the scheduling of the content propagation in
    the overlay network is much easier. Deciding on the correct
    block of information to transmit to another node is difficult
    without global information; the transm
  • it all comes falling down...
  • by Paul Crowley ( 837 ) on Thursday June 16, 2005 @06:16PM (#12836556) Homepage Journal
    Every time someone asks you for a block, you send them a new block, which is a random linear combination of all the blocks you have. This new block will almost always be useful to them. As soon as you get n blocks, where n is the number of blocks in the original file, you can reconstruct the original file. So bandwidth is never wasted sending a block the long way when the short way would do - you squeeze the maximum work from every hop.

    The really interesting bit is right at the end, almost as an aside:

    "In Avalance we use special sets of secure hash functions that survive network coding operations and consume very little computational resources"

    So even though each block is novel, they have a way for the receiver to ensure that it's a real piece of the puzzle. That's a hard problem indeed! So why isn't the solution part of the paper? Are they holding off from publishing that until the patent comes through?

Disraeli was pretty close: actually, there are Lies, Damn lies, Statistics, Benchmarks, and Delivery dates.