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Tor: A JAP Replacement 266

kid_wonder writes "Wired is running an article describing an answer to this previous /. story. Packets are sent through a network of randomly selected servers each of which knows only its predecessor and successor. Packets are unwrapped by a symmetric encryption key at each server that peels off one layer and reveals instructions for the next downstream node. As a 'connection-based low-latency anonymous communication system,' Tor seems to be the answer to JAP to allow anonymous networking activities of all kinds."
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Tor: A JAP Replacement

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  • by cytoman ( 792326 ) on Thursday August 05, 2004 @09:17PM (#9895677)
    ... the RIAA and the MPAA will be all over this, denouncing it and crying foul!


    • Well, as it stands, according to the author, if everyone from /. that just downloaded and tried the Tor client used it for P2P file transfer, the existing servers would buckle.
  • by Anonymous Coward on Thursday August 05, 2004 @09:18PM (#9895684)
    We are REPLACING japs now??!?!?
  • Freenet? (Score:5, Insightful)

    by pope nihil ( 85414 ) on Thursday August 05, 2004 @09:18PM (#9895687) Journal
    Isn't this onion routing thing exactly what freenet uses?
    • Re:Freenet? (Score:5, Informative)

      by MoonBuggy ( 611105 ) on Thursday August 05, 2004 @09:26PM (#9895743) Journal
      That's exactly what I thought (and I believe that we're right). What's interesting here though is that it claims to be low-latency, a quality rarely associated with Freenet and probably the primary reason that Freenet remains largely used by people who need/want _extreme_ anonymity rather than your average movie downloader wanting to avoid one of those nasty lawsuits.
      • No, Freenet doesn't use onion routing. Never has and doesn't today. It is impossible to both onion route a query and at the same time route it through a network based on local knowledge (since with onion routing the client has to map out the exact path of message in advanced, and the whole point with Freenet is that the client doesn't know where the message is going to go).

        There was discussion once upon a time about adding a couple of steps of onion routing before the Freenet routing starts - that would be
    • Re:Freenet? (Score:4, Informative)

      by elleomea ( 749084 ) on Thursday August 05, 2004 @09:39PM (#9895829) Homepage
      As far as I'm aware Freenet stores encrypted content on each node, not just routing requests through nodes.
    • by complete loony ( 663508 ) <{Jeremy.Lakeman} {at} {}> on Thursday August 05, 2004 @09:41PM (#9895841)
      Onion routing does just that, it is a method for picking an anonymous route. Freenet is a distributed database.
      In onion routing the client picks N nodes from the list of servers and encrypts using each servers public key. Then sends the data to the first server. In onion routing each packet of data contains the entire routing list, though it is encrypted in such a way that each node can only tell what the next node is.
      Each Freenet nodes caches data blocks based on demand. When a request arrives looking for a data block Freenet forwards the request to a node that has similar information until the correct block is found. Each freenet node only knows about the next and previous nodes, and the route is determined by the key you are searching for.
    • Re:Freenet? (Score:5, Informative)

      by Wesley Felter ( 138342 ) <> on Thursday August 05, 2004 @10:54PM (#9896206) Homepage
      Freenet doesn't use onion routing (last time I checked), but it does use the concept of sending messages through mutiple hops. But the main difference between Freenet and Tor is that Freenet is an anonymous publishing system and Tor is an anonymizing layer that can work with almost any application.
    • Re:Freenet? (Score:4, Informative)

      by 0x0d0a ( 568518 ) on Friday August 06, 2004 @12:12AM (#9896683) Journal
      Isn't this onion routing thing exactly what freenet uses?

      Not in the same form.

      Freenet allows posting of data, which does travel through multiple nodes, much like this one. It also allows retrieval of data. However, the two are separate operations. You don't establish a connection between the publisher of data and the reciever, which means Freenet tends to be unsuitable for things that require even remotely interactive latency. I think Tor might wind up being a bit high for, say, SSH, but it could easily be just fine for instant messaging -- two people that don't know each other by anything but pseudonyms and cannot trace each other can conduct conversations.
  • hmmm (Score:5, Insightful)

    by SinaSa ( 709393 ) on Thursday August 05, 2004 @09:19PM (#9895693) Homepage
    Tor - The internet onion!

    No, but seriously, the blurb says this is low latency, how that's the case, I fail to see. First client wants to send a HTTP GET or something similar via Tor, so every packet involved needs that info, plus a little bit extra to get it to the next node, plus a little bit more so the end node knows where it needs to be in the end on the return. So that's two extra little bits, then the stuff gets sent one node across which takes its info off and puts new info on.

    Where is the low latency here? All this peeling/adding layers to peel off must be fairly time consuming. I'll admit I quite like the idea, and as soon as I click Submit I'm going to download and try it, but I fail to see how this can be faster than say, InvisibleIRC (IIP) was.
    • Re:hmmm (Score:5, Informative)

      by dfelznic ( 8812 ) <(dfc) (at) (> on Thursday August 05, 2004 @10:01PM (#9895951) Homepage
      I am using tor right now to read slashdot as well as IRC and GAIM. Tor is not supposed to be as low latency as your normal connection. Security is a trade off the slight degradation in latency is worth the improved anonymity...

    • Tor is low latency compared to Mixmaster, which has a latency of around 24 hours.
    • Re:hmmm (Score:5, Informative)

      by jhoffoss ( 73895 ) on Friday August 06, 2004 @12:12AM (#9896682) Journal
      Tor achieves low latency because tunnels are created during connection setup, and that same tunnel is utilized for the life of the connection.

      I believe the encryption is layered on from the start, and peeling occurs at each transfer, not peel/crypt/peel/crypt/etc.

      I was surprised to see no one posted this earlier; the author of Tor gave a very good presentation at DEFCON last week, and I'll have to get out my CD with his presentation on it, but it's different from Freenet in a few ways. For one, apparently Freenet isn't totally free.

      As a side-note, the author is still working on a method to accept/sign-up/recruit primary [trusted] nodes.

    • Oh, and Tor is either "Tor Onion Routing" or "The Onion Router" (if I recall correctly.) I checked the site quick, too, and the slides from DEFCON and BlackHat are on his site.
  • by AbbyNormal ( 216235 ) on Thursday August 05, 2004 @09:21PM (#9895704) Homepage
    our East Asian readers, will readily endorse this new standard...Honestly, I guess not many people think about their acronyms before they are released to the public.
    • Why would East Asians have a problem with an acronym that also refers to Jewish American Princesses?
  • Not Like Freenet (Score:5, Insightful)

    by gclef ( 96311 ) on Thursday August 05, 2004 @09:22PM (#9895708)
    Wow. Lots of DefCon related stories.

    Anyway, for those asking, no, this isn't quite like Freenet. In TOR, you decide which points you want to send traffic through (and negotiate encryption keys with each one individually), and, unlike FreeNet, you can tunnel existing protocols over it (like, say http).

    There's a lot of promise here, but in his talk, he was looking for sites that had at least 1Mbps up & down speeds for nodes. This isn't quite like Peekabooty, in that right now they're not looking for everyone to run a middleman node.
    • Re:Not Like Freenet (Score:5, Interesting)

      by X ( 1235 ) <> on Thursday August 05, 2004 @09:26PM (#9895747) Homepage Journal
      What it is very much like is from Zero Knowledge Systems. Those guys already provided the patches to Linux to implement it, and had way more sophisticated protections (things to prevent discovery by timing and packet size analysis). Unfortunately, not may people used it, so it went bust. Now ZKS mostly does firewall software. :-(
      • Re:Not Like Freenet (Score:4, Interesting)

        by gclef ( 96311 ) on Thursday August 05, 2004 @09:32PM (#9895785)
        Yeah, he mentioned ZKS in his presentation. Their disappearing, and taking the network with them, is one of the reasons that he's BSD-licensing the code for this.

        Interestingly, one of the other reasons is that he managed to convince the Navy that others would use and trust the code (therefore making the Navy's use of it more difficult to detect) if those others could read the code and implement it themselves. I'm honestly kinda surprised (but happy) that the Navy agreed to it.
  • by Rosco P. Coltrane ( 209368 ) on Thursday August 05, 2004 @09:22PM (#9895711)
    to help Internet users surf the Web anonymously and shield their online activities from corporate or government eyes. The system is based on a concept called onion routing.

    I've just tried to set as http proxy but it doesn't work...
  • by hadesan ( 664029 ) on Thursday August 05, 2004 @09:25PM (#9895737)
    which is completely open source and avaialble to anyone who want's to download it?

    If the Navy is funding this project, don't you think they have already found a way of monitoring it?

    • Sure, monitor one of the known ends and dumping the packets to file for cracking later. Of course, the main question is how practical would it be to do? If the encryption has a good algorithm, then it could be too computationally expensive to decrypt meaningful amounts of data. If the algorithm is weak, then near real-time monitoring might be practical. Besides, reading the article, it's being set up more to help intelligence spooks do research without tipping everybody else in the world off. Not inclu
      • Not including terrorists and foriegn goverments, lots of entities would love to know what the US intelligence community finds interesting.

        Your point here is the most interesting. I think you have it right on the ball here. I am sure there are a number of large corporations that would love to know about any potential future flare ups in certain regions so that they can get their tenders in for redevelopment work and other such things in before their competition has even heard about it.

        I suspect 20 minut

    • To quote Paul Syverson from his PET talk:
      "The man needs your cover traffic just as much as you need the man for his cover traffic.."
    • If the navy has figured out how to factor the product of two large primes quickly, then we've got big problems
      that reach far beyond this tor thing. If not, then this is probably okay. =)
  • by shadowmatter ( 734276 ) on Thursday August 05, 2004 @09:32PM (#9895786)
    Schemes like this to make p2p anonymous have been around for awhile. The problem is that such systems have very high end-to-end latency, so in practice it's not really ideal for a constantly evolving network -- like peer-to-peer. A scheme similar to this, using mixes, is Tarzan []. From its ACM paper:

    Tarzan is a peer-to-peer anonymous IP network overlay. Because it provides IP service, Tarzan is general-purpose and transparent to applications. Organized as a decentralized peer-to-peer overlay, Tarzan is fault-tolerant, highly scalable, and easy to manage.Tarzan achieves its anonymity with layered encryption and multi-hop routing, much like a Chaumian mix. A message initiator chooses a path of peers pseudo-randomly through a restricted topology in a way that adversaries cannot easily influence.

    Such systems right now have too high a latency and too much overhead (such as a peer sending "noise" into the network when not having the need to send any real data, just to deter packet analysis) that they aren't terribly practical... for now. So you most likely won't see the technology bundled in the next KaZaA, BitTorrent, etc., but we'll see what the future holds.

    - sm
    • Another of the problems with these approaches (besides the need to send cover traffic, as you mentioned) is that pseudo-random path selection may not be random enough. Certainly an "omnicient" adversary could run various correlations to determine who is sending data to whom, and it becomes very difficult to make convincing arguments as to whether more realistic adversaries can glean information from the traffic they observe. If there's one lesson we've learned from crypto research, it's that smart mathema
  • too bad... (Score:3, Funny)

    by night_flyer ( 453866 ) on Thursday August 05, 2004 @09:33PM (#9895790) Homepage
    we did have this back in 1941
  • by astrashe ( 7452 ) on Thursday August 05, 2004 @09:34PM (#9895799) Journal
    What happens when people start doing bad stuff with the tor system? You know it's going to happen...

    The model is bad, because the people running the servers (like the old cypherpunk remailers) are supposed to provide services for free, out of the goodness of their hearts, and take the heat when people do malicious stuff with the network.

    It seems to me that it's not a bad technical system, but that it fails when you start to think about the social and economic realities of the net.

    • by gl4ss ( 559668 ) on Thursday August 05, 2004 @10:10PM (#9895983) Homepage Journal
      like spammers taking advantage of a fairly open email system?
      sorry, couldn't resist.

      still, email works.

      these systems are mostly meant for distributing the possible heat anyways.. and making it impossible to pinpoint it on anyone spesific(because you don't even know what you're routing). the problem is when there's some naive people running these that start crying once they figure out what's anonymity mostly needed for(like freenet, they make a system that's practically meant for distributing banned materials and start crying when they realise that the materia had reasons to be banned in the first place..)..

      for a normal user though these just mean assurance of that if RIAA/MPAA starts being veeery aggressive about p2p people will switch to some more advanced version of p2p even if it comes with severe performance(speed) hit.
    • "What happens when people start doing bad stuff with the tor system? You know it's going to happen..."

      When doesn't it happen? Freedom of Speech comes to mind. It all sounds great until people find out the KKK are protected. Everything's like that. The best you can hope for is it does more good than harm.
    • I'm concerned that negative impacts could be used as ammunition for attempts to ban anonymous systems. I'd rather have a more strongly entrenched group of people using anonymizing software before seeing something released that can be used to attack systems anonymously.

      Ah, well.
  • by Positive Charge ( 592093 ) on Thursday August 05, 2004 @09:36PM (#9895810) Homepage
    (I know because I submitted this article too.)

    1. The Navy is bankrolling the development, presumably to allow government employees to surf around without leaving ".gov" and ".mil" ip addresses in logs.

    2. JAP supposedly has a German Government implanted backdoor that this one shouldn't because it's open source.

    I think that the US Government is bankrolling it to piss off the Chinese.
  • by Gannoc ( 210256 ) on Thursday August 05, 2004 @09:38PM (#9895821)

    This technology will certainly become a favored tool of terrorists trying to avoid the justice of the Bush administration.


    The MPAA.
  • by Anonymous Coward
    I'm not sure yet what it does, but I'm thinking of calling it the Heuristic, Orthogonal, Non-Knuth-approved, Yielding algorithm.

    HONKY, for short. I guess that name won't be a problem, will it? I mean, since JAP seems to be okay...
  • by putaro ( 235078 ) on Thursday August 05, 2004 @09:43PM (#9895851) Journal
    I think it's great that the Navy is funding this. Now, where are the wire tap hooks? [] I always enjoy the way the government exempts itself from its own rules.
  • Nothing new (Score:3, Informative)

    by Anonymous Coward on Thursday August 05, 2004 @09:53PM (#9895916)
    Something named "My own private Idaho", an anonymous remailing software from 1996-1998, did (and is still doing) exactly the same thing, with PGP integration, and server key publication.
    • This isn't really a mail anoymizer. There are better mail mixers (like mixmaster) out there. Because latency isn't that big an issue for mailers, adding a 3 hour or so delay isn't a big deal to a mail anonymizer. Adding that kind of latency to http is unacceptable, so you can't use the same system to anonymize http as smtp, unfortunately.

      Because of that, you can build a better anonymizing system for smtp because you can avoid timing attacks more easily. If you're interested in anonymous mail, though,
  • by brett42 ( 79648 ) on Thursday August 05, 2004 @09:56PM (#9895931)
    From the couple of days I spent actually working in my highschool cisco class, I remember each router in a path is supposed to be able to optimize the route a packet is sent on by using local information and the packet's final destination. From what I gather from the limited technical details in the article, this protocol would require knowledge of the entire route at the initial node to handle the 'onion layer' encryption.

    Is there some way of optimizing a path through a given number of nodes without keeping huge amounts of information about latency on every two nodes, or is this just bouncing the packet around for a while for anonymity and accepting the added latency, plus possibly the time it takes to detect and resend packets when one node in a path suddenly goes dead, making the custom-encrypted packet worthless?
    • by Wesley Felter ( 138342 ) <> on Thursday August 05, 2004 @11:08PM (#9896294) Homepage
      From what I gather from the limited technical details in the article, this protocol would require knowledge of the entire route at the initial node to handle the 'onion layer' encryption.

      Correct. The sender wraps the whole onion, and each router removes one layer.

      Is there some way of optimizing a path through a given number of nodes without keeping huge amounts of information about latency on every two nodes, or is this just bouncing the packet around for a while for anonymity and accepting the added latency?

      It's more like the latter. Optimizing for performance tends to be at odds with anonymity.
  • Why is this so tough for people to "get" ?
    • > Why is this so tough for people to "get" ?

      Maybe because you say right on your website [], "Don't post this to slashdot. You will murder my cable modem."

      Who knows how many truely brilliant ideas have languished in obscurity because their author was afraid of a slashdotting... Surely thousands -- no, millions...
  • Mixmaster for TCP? (Score:3, Insightful)

    by kinema ( 630983 ) on Thursday August 05, 2004 @10:14PM (#9896003)
    This sounds a lot like an implementation of Mixmaster [] for TCP.
  • by KillerCow ( 213458 ) on Thursday August 05, 2004 @10:14PM (#9896010)
    This sounds like a reinsertion of all the technology that has gone into anonymous mailers over the years (see MixMaster [].) I hope that they aren't re-inventing everything and repeating the same mistakes. The existing technology should be mostly portable from the application layer to the session or layer.

    I was at a presentation by the guy behind MixMaster and was impressed by all the thought that has gone into the various generations of the application. They even had it generating fake messages so you can't do traffic analysis.
    • This sounds like a reinsertion of all the technology that has gone into anonymous mailers over the years

      Not a reinvention, but it's based on Mix nets. These people have been working on anonymity networks for years, and have done a lot of research into building solid systems from ideas that are largely theoretical or ad-hoc. Look online for Syverson's publications and you'll see what I mean.

  • No one can replace the Jewish American Princess, what with her snooty attitude and come-hither glances. Come on.. baby needs a new BMW
  • Onion Routing (Score:5, Interesting)

    by dachshund ( 300733 ) on Thursday August 05, 2004 @10:36PM (#9896117)
    Onion Routing [] has been around for several years. Tor is an effort to make the original protocol more practical. It replaces several nice features from OR, specifically the notion of "reply onions", which allowed message recipients to route replies back to the sender without learning the sender's identity. Instead, TOR recommends a form of "rendezvous point" where receivers send messages to be routed back to the sender. It's not as elegant, and the security is not necessarily as strong, though it is more practical.

    It's important to note that there are some statistical attacks on both of these systems, and none of them are very secure for long communication sessions when group membership churns, as in a peer-to-peer network.

  • This sort of thing is of little use to anyone but criminals. Yes, I realize that you shouldn't necessarily ban or restrict something that has legitimate uses simply because it's also useful for criminals, but I think it's worth asking whether or not something like this would really be a net benefit to society. I know the Freenet crowd likes to make constant reference to oppressive governments, political dissidents, etc., but does anyone really think that the ratio of illegal porn and illicitly-traded copyri
    • *chuckle* You kidding? Something like this would be a boon to IT departments in companies whose edge depends on their communications structure... particularly ones whose salesmen are field agents and road warriors.

      Business is cutthroat. Communications in one company, if intercepted, can give other companies the edge. One layer of protection isn't enough, but then again, encrypting everything in one layer gives the would-be cracker that much more difficulty getting to the valuable blood of business.

      • If you think that your business competitors can break modern encryption algorithms like AES, I'd be really curious to hear what sort of business you're in.
        • Well, first of all, nothing is truly invincible to a determined person. AES is currently a real bitch to decode, but it's a fallacy to assume that because you have AES, you'll never need to worry about security again. DES would have stumped the hell out of anyone during WW2 days; it's not impossible these days, especially with smaller bit sizes. AES is the trend du jour of encryption algorithms... but only until it's broken. If someone breaks the first encryption algorithm, I want the "plaintext" to be

      please to trade my freedom for the appearance of security...
    • but does anyone really think that the ratio of illegal porn and illicitly-traded copyrighted material to legitimate use isn't astronomical?

      That means little.

      The same is true of P2P networks.

      P2P file distribution is simply both cheap and an effective way of offloading distribution costs onto all consumers -- it is as elegant a concept as the free market.

      Currently, much of the use of P2P file distribution happens to be for copyright-infringing content and porn. This is not because of anything inherent t
  • by andymurph ( 803194 ) on Thursday August 05, 2004 @11:17PM (#9896348)
    ... The Register [] broke this story ages ago: Here [] and Here []. Why is /. so reluctant to credit these guys for the tech stories they so often break? Jealousy?
  • Zero Knowledge Systems provided commercial onion skin routing for quite some time.

    Since heavily-used onion-skin-routing can make traffic analysis a pain and is one of the best anonymity mechanisms we have, I'm certainly cheering Tor on. If you don't like your network usage being monitored, be it web browsing, newsgroup reading, email, or chatting, onion-skin routing is a Good Thing.
  • by xiando ( 770382 ) on Friday August 06, 2004 @01:40AM (#9897009) Homepage Journal
    It's been quite a while since I made my site LinuxReviews [] IPv6 Ready []. This has made me look at the IPv6-ready Web Server list [] from time to time and sadly there is very few sites out there that are IPv6 capable.

    It is nice to know Tor supports standard protocols like http://. But do you really believe those "Tor Ready!" websites will start popping up any time soon? I don't think so. The majority of todays websites do not validate [], doesn't support IPv6 and many don't even render correctly in the majority of web browsers. Will Tor-Ready be prioritized higher by the average webmaster than these and other more serious issues?

    I am also very skeptical to the bandwidth requirements and the latency. My Ipv6 connection gives me full bandwidth, but I do notice that connections going through the tunnel are, in fact, much more latent than normal native Ipv4 connections. So why would I prefer to visit some website using Tor when the real difference is a longer loading period? Yes, what the author says about low latency may be true. It may have less latency than alternatives, but do not try to tell me I won't notice significantly higher latency if I try to IRC through a TOR connection.

    People are talking about Ipv6 becoming standard in 5-6 years, I will be amazed if tor still exists at that point in time and even more amazed if it's actually implemented on more than 0.0001% of the Internet's services.
  • So.. basically, set up a NAT or proxy server rather, and let the internet users of the world use that (+IPSec)!?

"We don't care. We don't have to. We're the Phone Company."