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Networking IT

Trackerless BitTorrent Beta Posted 432

jgarzik writes "BitTorrent development is occuring at a furious pace. At the beginning of May, an Azureus update added distributed tracker and database features. Yesterday, Bram updated BitTorrent to include support for trackerless torrents in the new BitTorrent 4.10 beta."
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Trackerless BitTorrent Beta Posted

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  • So... (Score:5, Insightful)

    by Anonymous Coward on Wednesday May 18, 2005 @10:24PM (#12573587)
    Will this eventually leave the BSA and others with no BT tracker sites to shut down, so that their only option will be to go after end users or to DOS the P2P networks themselves?
    • Re:So... (Score:5, Informative)

      by TrevorB ( 57780 ) on Wednesday May 18, 2005 @10:27PM (#12573607) Homepage
      It sounds as if the .torrent files still need to be downloaded or stored somewhere. It's just the middle step of the tracker that can (optionally) be eliminated.
      • Re:So... (Score:5, Informative)

        by saskboy ( 600063 ) on Wednesday May 18, 2005 @11:07PM (#12573885) Homepage Journal
        Essentially, the client is now also a simple tracker. You still need a torrent file, you just don't have to set up a tracker now, just open your client, like you'd normally do for Kazaa or other file sharing programs.

        Here is the bittorrent.com explanation:

        BitTorrent Goes Trackerless: Publishing with BitTorrent gets easier!

        As part of our ongoing efforts to make publishing files on the Web painless and disruptively cheap, BitTorrent has released a 'trackerless' version of BitTorrent in a new release.

        Suppose you bought a television station, you could broadcast your progamming to everyone in a 50 mile radius. Now suppose the population of your town tripled. How much more does it cost you to broadcast to 3 times as many people? Nothing. The same is not true of the Web. If you own a website and you publish your latest video on it, as popularity increases, so does your bandwidth bill! Sometimes by a lot! However, thanks to BitTorrent the website owner gets almost near-broadcast economics on the web by harnessing the unused upstream bandwidth of his/her users.

        In prior versions of BitTorrent, publishing was a 3 step process. You would:

        1. Create a ".torrent" file -- a summary of your file which you can put on your blog or website
        2. Create a "tracker" for that file on your webserver so that your downloaders can find each other
        3. Create a "seed" copy of your download so that your first downloader has a place to download from

        Many of you have blogs and websites, but dont have the resources to set up a tracker. In the new version, we've created an optional 'trackerless' method of publication. Anyone with a website and an Internet connection can host a BitTorrent download!

        While it is called trackerless, in practice it makes every client a lightweight tracker. A clever protocol, based on a Kademlia distributed hash table or "DHT", allows clients to efficiently store and retrieve contact information for peers in a torrent.

        When generating a torrent, you can choose to utilize the trackerless system or a traditional dedicated tracker. A dedicated tracker allows you to collect statistics about downloads and gives you a measure of control over the reliability of downloads. The trackerless system makes no guarantees to reliability but requires no resources of the publisher. The trackerless system is not consulted when downloading a traditionally tracked torrent.

        Although still in Beta release, the trackerless version of BitTorrent, and the latest production version are available at http://www.bittorrent.com/ [bittorrent.com]
        • by Anonymous Coward on Thursday May 19, 2005 @02:05AM (#12574850)
          By distributing the tracking, this helps to minimize the damage should the original publisher go off-line. This does absolutely nothing for hiding your IP address.

          The *AA can still nail you for being a distributor of unauthorized Copyrighted material if you use Bittorrent. You are of course giving out copies to other users; so all the *AA needs is a list of IP addresses that are in the swarm. Granted, the *AA hasn't really done this. But if there's one thing that they have shown is that they are extremely motivated to find people who are involved, and hit them with a bill for a $2-3K settlement.

          With an economic bounty like that, the only thing the Lawyers of the *AA are lacking is a way to automate the technology. From what I hear, that technology is coming. Supposedly some of it is in beta test now.

          The only defense one might hope for in the U.S. is a scheme which added plausible deniability. That's not here yet with BT; and even if implemented, would undoubtedly result in a slowdown of downloads.

          Personally, I think your best bet if you are concerned is to use an offshore ISP.

      • Re:So... (Score:5, Interesting)

        by Cramer ( 69040 ) on Thursday May 19, 2005 @01:42AM (#12574786) Homepage
        If he's doing things exactly like Azureus, then a torrent file can be retrieved from anyone known via DHT to be part of that swarm... it's called a magnet url.

        This is the reason why DHT, as the monkeys released it, is a Bad Thing(tm). They should've err'd on the side of caution and assumed torrents were "private" unless explicitly marked otherwise. Because they added the "private" flag to the info dictionary, sites cannot retroactively privatize their torrents -- it changes the info_hash, which is the exact reason why the monkeys put it there (where it technically doesn't belong.)
    • Re:So... (Score:4, Interesting)

      by ProfaneBaby ( 821276 ) on Wednesday May 18, 2005 @11:13PM (#12573915)
      The BSA, MPAA, RIAA only has to go after a handful of very large network providers before then can put a large dent into various P2P networks.

      Hitting some of the larger college campuses would be a good start. Some colleges will fight, but until the precedent is set, others will block, and the highest bandwidth users will be offline.
    • Re:So... (Score:3, Informative)

      by AirShark ( 768815 )
      They're already going after end-users. One of my buddies just got mauled by Columbia Pictures.
    • by anandsr ( 148302 ) on Thursday May 19, 2005 @06:19AM (#12575829) Homepage
      I don't know why a trackerless mode was chosen, I thought that the efficiency of BT is due to the centralized tracker. I think it would be better to provide redundancy to the tracker function by adding a super tracker functionality.

      Actually the centrallized tracker is a very important thing. It decides who downloads what. Without the central tracker the effort will not be that synchronized.

      I was expecting the development to be towards making the tracker redundant, with creating a super tracker, that would track the tracker.

      Also the .torrent file is the real problem in hosting files. Its not as easy as just providing one directory and every file in that directory gets shared. Ofcourse there are benefits also to the .torrent file when we want to serve a whole directory as a single torrent. An approach where both kinds of things can be done will be better than a single method.

      Also the Emule has it better that it can determine that multiple names of a file are actually the same file, based on the same Hash.

      I would think it would be better to have super trackers track the trackers, with multiple super-trackers tracking the same tracker. And each super tracker would be tracking multiple trackers. Super trackers would provide the search capabilities, and would share tracker information among themselves. They would also provide tracker redundancy. They would also be able to determine if the different file names are in fact the same file, and merge several trackers into one.

      I think the peers with good bandwidth and with maximum completed parts would become the tracker. The benefit of being the tracker would be that you get the file faster, because the tracker would obviously give itself the benefit. Then when the tracker has completed its own file. A new tracker would be selected.

      What do people here think?
      • by Taladar ( 717494 ) on Thursday May 19, 2005 @06:57AM (#12576012)
        The Tracker does not decide who downloads what. It just has a list of IPs. Each client decides what it downloads but it uploads only/better to the clients that send to it faster than the others. That way uploading clients get the biggest part of the bandwidth and clients that leech only get the rest that is not needed by one of the others.
      • by thing12 ( 45050 ) on Thursday May 19, 2005 @07:34AM (#12576308) Homepage
        Also the .torrent file is the real problem in hosting files. Its not as easy as just providing one directory and every file in that directory gets shared. Ofcourse there are benefits also to the .torrent file when we want to serve a whole directory as a single torrent. An approach where both kinds of things can be done will be better than a single method.

        Bittorrent isn't a "share all the files on my hard drive" system. It's a distribution system for content publishers. It will most likely never be the former because that's how you get the MPAA, RIAA, etc on your back. If you want a list of content publishers use Google.

        Also the Emule has it better that it can determine that multiple names of a file are actually the same file, based on the same Hash.

        There's never any danger of downloading multiple versions of the same file because you download the torrent file from the publisher's website - not the system. That torrent connects you to one or more peers, the mini-trackers, which are presumably operated by the publisher. And then it's just standard bittorrent stuff.

        It's good way to publish legitimate content. It's not a good way to distribute illegal content. First of all the torrent has a record of your peer IP addresses. So, all the lawyers need to do is have the peers listed in the torrent shut down -- then the torrent is useless. Sure, you could hide for a while using zombie windows boxes as your "master" peers, that's one level of indirection. But as they become unavailable you need to distribute new torrent files with fresh peer lists. Maybe that's not a problem, but it seems like more trouble than it's worth.

        If you want a share-all-my-files p2p bittorrent, try eXeem (or eXeem Lite).

      • You left out the all important super tracker tracker. We obviously need a super tracker tracker to track the super trackers that are tracking the trackers. Are you keeping track of all this?
  • by autophile ( 640621 ) on Wednesday May 18, 2005 @10:27PM (#12573605)
    See you in Guantanamo, "Bram".
  • Damn it! (Score:5, Funny)

    by Anonymous Coward on Wednesday May 18, 2005 @10:27PM (#12573610)
    I hate it when I squeeze harder and things start to slip through my fingers.
  • Hmm... (Score:5, Funny)

    by conchobar0928 ( 865821 ) on Wednesday May 18, 2005 @10:27PM (#12573614)
    Is it just a coincidence that this enhancement has come the day before the new Star Wars movie?
  • by Neoncow ( 802085 ) on Wednesday May 18, 2005 @10:28PM (#12573615) Journal
    I thought the advantage of BT was the strength in large numbers approach? As more people join the swarm, there is more excess bandwidth. And the overall speed increases, right?

    If you lower the cost of entry to producing a BT release, won't that mean more .torrent file swimming around? With the increase of different torrents everywhere, won't that dilute the power of BT?

    Is it legal to post only in questions?

    • by F13 ( 9091 ) on Wednesday May 18, 2005 @10:45PM (#12573733)
      Is it legal to post only in questions?

      Yes, Yes it is. The Independent Thought Police have been dispatched.

      Have a nice day.

    • While this makes it easier to create a .torrent, most users don't know how to do so in the first place, and even if know how, they would still need to put the .torrent somewhere, and its the torrent's popularity that determines if it lives or dies. If there is a better, more popular torrent, then it is unlikely that many people would go for the second one.

      I guess what I"m saying is -- torrents are a popularity contest. You can't win by being a poser.
    • by Jeremi ( 14640 ) on Wednesday May 18, 2005 @11:12PM (#12573905) Homepage
      If you lower the cost of entry to producing a BT release, won't that mean more .torrent file swimming around?

      Hopefully... allowing more people to post more content is one of the project's goals.

      With the increase of different torrents everywhere, won't that dilute the power of BT?

      No, because the uploaders for a given file consist only of the people who have previously downloaded that file. So no matter how many files are "out there", the total bandwidth available to distribute any particular file is always proportional to the number of people interested in that file.

      File-A's popularity won't leech bandwidth from File-B's swarm, because File-B's swarm wasn't providing any bandwidth for File-A in the first place.

      • by eraserewind ( 446891 ) on Thursday May 19, 2005 @12:16AM (#12574371)
        I think you missed the point of the question. What if there are dozens of torrents for the "same" file (e.g. britney.mov) Can the different torrent swarms somehow know about each other or does each torrent divide the potential members of the swarm into non-communicating groups with lower bandwidth?
        • by rusty0101 ( 565565 ) on Thursday May 19, 2005 @02:05AM (#12574846) Homepage Journal
          There are actually two possible questions out of this, "Two shares with the same name, but are different files." and "Two sources of the same file, shared seprately."

          Lets say you and I both recorded the latest Britney_Spears story on ET. We each grabbed from the first frame of the story as our recordings captured it, to the last frame of the story. It happens the there was a comercial break in the middle of the story, which we have each clipped out. However our clips are not identical, and if we are both capturing from an analog source, our actual files will be different. Even if we both share the file as 'ETBritneyInterview.mpeg2' our file hashes will be different, so there will be no collision.

          Next up... Joe is a fan of Ubuntu Linux, and tracks down an ISO file for it. Puts it on his web server with a .torrent file for it, then advertizes the .torrent file on his blog. Al, Bob, Cathy, Doris, Plauge, Faith, and Garth all decide to download a copy. Some because he is making it available on his blog, others because they saw a reference to it on hos blog, but decide to go to the source and download the ISO from there. The transactions that are using the .torrent file from Joe's blog are not going to be sharing transfer space with the transactions from the official torrent site.

          Last up, I create an ISO for some new distribution of Linux, and create a trackerless .torrent file for it, put the iso and .torrent on my web server, and link to the .torrent in my blog. Heather downloads the .torrent as part of her collection of that ISO, likes the file, so she puts my .torrent on her server, linking it with a blog entry, then leaves her client sharing the .iso file. In this situation, both of us would be sharing the bandwidth of distributing the .iso.

          Hope that addresses your question.

  • by Fruny ( 194844 ) on Wednesday May 18, 2005 @10:31PM (#12573641)
    I wonder what's going to stop **AA from shutting down the login servers. Sure, there might not be trackers to shut down, but a network is no good if nobody can join it. How do you expect to find out who your "peers" are otherwise?
    • by ErikTheRed ( 162431 ) on Wednesday May 18, 2005 @11:46PM (#12574140) Homepage
      I wonder what's going to stop **AA from shutting down the login servers. Sure, there might not be trackers to shut down, but a network is no good if nobody can join it. How do you expect to find out who your "peers" are otherwise?
      Seed from a country that doesn't have or doesn't enforce copyright laws. Then let the swarm take over for the rest of the world.
    • Bittorrent isn't designed for distribution of subversive or otherwise contraband content; it's designed to take the load off the backs of legitimate distributors of large files. There's nothing stopping the *AA from shutting servers down, and to the best of my knowledge this feature was not created with the intent of making it difficult for anybody to do so. Bittorrent might be optimal for quickly getting large files, but it isn't intended to protect anybody from anything; for that, you'll want to look into

  • How does it work? (Score:4, Insightful)

    by logik3x ( 872368 ) on Wednesday May 18, 2005 @10:31PM (#12573644)
    How does this work... how do you find peers to download from? Are they included in the .torrent file? IF so ain't that a big risk... if MPAA start collection peers informations? I guess it's encrypted but it can always be broken.. anyways if anyone have more info on how it actually works please inform me :P
    • Re:How does it work? (Score:3, Informative)

      by MrDomino ( 799876 )

      Bittorrent isn't intended to protect your identity. It never was. The fact that it's commonly used for activities that might get people in trouble is just due to lack of a poweful, easy-to-use solution in the arena of programs that do protect your identity (see: Freenet [freenetproject.org], Tor [eff.org], and MUTE [slashdot.org]), and possibly in part to bad planning on the part of an increasingly fragmented and confused base of illegal file-sharers.

  • by Sv-Manowar ( 772313 ) on Wednesday May 18, 2005 @10:32PM (#12573645) Homepage Journal
    I'm really glad to see this coming in the mainstream BitTorrent client. At the moment it can be hard to use the distributed tracking system because of its dependence on Azureus as a client. A lot of people have been making noise about this, and hopefully now that its in the main client, the developers of the other BitTorrent clients will make implementing support for this more of a priority.
  • by banuk ( 148382 ) on Wednesday May 18, 2005 @10:32PM (#12573650)
    ...what happened to btefnet et al? I mean the MPAA could still shut the site down b/c they were hosting the torrent file right?
  • by KarmaOverDogma ( 681451 ) on Wednesday May 18, 2005 @10:33PM (#12573656) Homepage Journal
    I think we'll see two things:

    1) **AA will squirm for a while
    2) **AA will work harder than before to moniyor and restrict user rights on the internet, via congressional purchasesing, er, I mean lobbying.

    I think #2 will ultimately be futile in that it will not slow their loss of control over media content distribution (and copyright violation) but it will make life unpleasant for many...
  • by btk667 ( 722104 ) on Wednesday May 18, 2005 @10:43PM (#12573719)
    This is realy the cat and mouse game at it's best. BitTorrent is getting better each day. While the RIAA and MPAA is closing the hosting website, Attacking ISP from around the globe, etc.

    Is this a combat to the death ?

    I guess nothing will beat private exchange ? (DRM)

  • by Richard Allen ( 213475 ) on Wednesday May 18, 2005 @10:44PM (#12573729)
    Went to download an upgrade bittorrent.

    I was a bit surprised that the download for the upgrade didn't have a bittorrent option. Isn't that ironic? or did I miss the link on bittorrent.com?
    • by Anonymous Coward on Wednesday May 18, 2005 @11:15PM (#12573925)
      It's the classic question. How do you make "make"? How do you untar "tar"? How do you decompress "gzip"? How do you compile "gcc"?

      The answer in all cases is to work around the problem by not storing the code in the format it supports. eg: make comes with a shell script to build the binary. gzip is distributed in .Z and non-compressed forms, as well as a shar file. tar is distributed as a shar file. etc. etc. etc.

      BitTorrent isn't all that large, so there isn't much to be gained by distributing it that way. It's best at file packages in the multi-hundred megabyte and larger range. The largest BT download is only around 1 MB ...
  • by Saeger ( 456549 ) <(moc.liamg) (ta) (jllerraf)> on Wednesday May 18, 2005 @10:52PM (#12573780) Homepage
    Simply because the torrent websites no longer have to host the .torrent files, or run the tracker, doesn't mean that the RIAA/MPAA can't still sue the domain owner(s) for technically offering pointers to pointers (unless you're untouchable [piratebay.org] in, say, the netherlands). So BT is now a little more distributed, like eDonkey, but that didn't stop ShareReactor, ShareConnector, or FileNexus from being shutdown either.

    What's needed is some kind of distributed HTTP overnet that works; that can handle dynamic content semi-intelligently, and MUCH faster than freenet/frost sites.

  • so quick question... (Score:3, Interesting)

    by william_w_bush ( 817571 ) on Wednesday May 18, 2005 @10:52PM (#12573782)
    is the publisher traceable? like is the ip address in the .torrent, cause that might be a bit of a giveaway.

    not sure how it'd work otherwise, but this gives each torrent a single responsible party for its uploading. on the plus side they could limit who has access to the download client tables to people who need it and upload valid.

    curious, and no im not just using it for legitimate torrents, but i pay for my cable and id rather keep stuff on my file server than a tivo with a crappy interface.
  • ... here's some more info on this, assuming it's compatible with Azureus:
    • Peers are located with an overlay network based on the Kademlia [google.com] algorithm, with small tweaks.
    • You can enter the overlay network either by a central seed node (which is needed only one per install) or by asking some of your peers on some other torrent for their DHT addresses.
    • Azureus has a magnet link system, where given a 'magnet link' containing the infohash of the torrent, it will use the DHT to find a peer and download the .torrent file from them. Hopefully the official client will get this as well.
    • Yes, this really does work. Grab a copy of Azureus and enter magnet:?xt=urn:btih:MC2ZPC2TCW2TJTY5DSSOMDX533EPXV FU [magnet] (no spaces!) into the open location box to try it out. Be sure to wait for the dot on the bottom to change from yellow/"Initializing..." to green, and open your UDP port (same as torrent data port by default)
    • Check out the Azureus wiki [aelitis.com] for more info.
  • by pyite69 ( 463042 ) on Wednesday May 18, 2005 @10:59PM (#12573827)
    That would be much more useful... if each socket connection does a key exchange. Much harder for your ISP to snoop.
  • by Anonymous Coward on Wednesday May 18, 2005 @11:03PM (#12573855)
    Someone should write an extention for Firefox that gives the download manager bit torrent support. Combined with trackerless torrents, it's likely a lot more sites will start using torrents.
  • Application of DHTs (Score:4, Informative)

    by Spezzer ( 101371 ) on Wednesday May 18, 2005 @11:15PM (#12573928)
    I just learned about Distributed Hash Tables this past semester and thought they were really cool. On the bittorrent page linked in the blurb, it mentions the use of a DHT in order to do the join/lookup required for locating peers.

    If you are interested in how it works, you can check out http://en.wikipedia.org/wiki/Distributed_hash_tabl e [wikipedia.org] for more info on them and links to example DHT implementations (such as CAN, Chord, and Kademlia).
  • Even better: Dijjer! (Score:3, Interesting)

    by volkris ( 694 ) on Wednesday May 18, 2005 @11:42PM (#12574103)
    A much more interesting but similar system is the dijjer project at dijjer.org [dijjer.org].

    Like this it's a distributed publishing system without any sort of tracker, but without torrent files either. In dijjer you make requests from your web browser through a proxy server that's your interface to the rest of the system.

    It's different in that all of the data being distributed exists in a single system, not in grouped systems of people interested in the same file. Therefore there's a lot less concern about there being too few peers signed on to make the system work.
  • by CyberZCat ( 821635 ) on Wednesday May 18, 2005 @11:57PM (#12574232)
    Before it took time, patence and know-how to get a release up and going. Now it's suddenly going to become so easy to distribute stuff with BitTorrent that people will start putting up fake virus/spyware/corrupt files because it won't take any time or knowledge to do so. Releases distributed with BitTorrent has always excelled in their quality when comparred to their P2P (think Kazaa) counterparts. Now BitTorrent will suddenly become as bad as Kazaa, bogus files, destorted music... it was good while it lasted, BitTorrent.
  • by Jagasian ( 129329 ) on Thursday May 19, 2005 @12:26AM (#12574439)
    Bittorrent's beta release is not really trackerless. Instead it implements a distributed tracker very similar to the one used in Azureus. In fact, both make use of the Kademlia distributed hash table routing algorithm, but both implementations are different just enough to make them incompatible with each other.

    This begs the question, why wasn't this beta postponed until its implementation could be made compatible with the already existing distributed tracker implementation in Azureus? Both projects are open source and both are written in high-level programming languages: Python and Java respectively.

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