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Can Poisoning Peer to Peer Networks Work?
andrewchen writes "Can poisoning peer to peer networks really work? Business 2.0 picked up my research paper from Slashdot
and wrote an article about it. In my paper, I argue that P2P networks may have an inherent "tipping point" that can be triggered without stopping 100% of the nodes on the network, using a model borrowed from biological systems. For those who think they have a technical solution to the problem, I outlined a few problems with the obvious solutions (moderation, etc.)."
Most of us who have been on P2P looking for files have been used to the fact that a large number of users are misconfigured (their firewall blocks your incoming request but heppily tells you they have the file you want) or are trading crap quality files. At that point you resort to brue force and using a bot to just grab everything it can to a large holding drive... a 40gig ide is dirt cheap and can easily hold the results of running a bot searching for "radiohead mp3" and grabbing EVERYTHING it finds over the course of about 3 days. but then you have to manually go in and delete all the crud, cruft and garbage. It's still faster than the old days of IRC trading but the signal to noise ratio has always been really bad.
Granted poisining it can start to drive away the gimmie-gimmie crowd or the newbies.. but the hardcore and old-timers will stay and simply find a way around it. Hell a group of about 100 of us now have our own private open nap network going and we have only high quality known good files. any clients connecting not sharing or sharing crap are instantly banned/blackballed... so we do the moderation thing.. with a side requirement that you must be asked to join and prove your worthyness to us. Maybe that will be the direction P2P will go... back to the roots of IRC where you had to prove your worthyness, ratios were encforced, and real people made decisions to keep out the troublemakers...(RIAA) granted you dont get 30 bajillion users that way, but then you dont have to spend a night and 10 gig trying to find that song or file you want.
Do not look at laser with remaining good eye.
The answer is quite simple, and would be very difficult for the sabateurs to subvert.
GPG signatures (which BTW include a checksum) of content, with said signatures refering to an online alias rather than a real person (thereby maintaining anonymouty).
A web of trust is formed, in which HollywoodDude is known and trusted, and has signed RipperGod's key, who in turn has signed FairUsers key, and so forth.
Provide a separate way of obtaining the keys (e.g. multiple independent websites, multiple independent keyservers, and so forth), and people can simply filter out anything submitted by untrusted users. If something submitted by someone outside of the trust ring, and someone who is trusted sees the item and determines that it is worthwhile/good/whatever and not a decoy, they could sign the item themselves.
Gaining trust would of course take time, probably requiring many worthwile submissions, but that is true in real life anyway, so why should it be any different online.
If someone violates their trusted status (or their private key is stolen, which BTW would be a violation of the law), others in the ring of trust could revoke their trusted access and blacklist their signature.
It isn't as convinient as just being able to share something with little or no thought, but it is emminently doable, and there really is no straightforward way to undermine such an approach.
The Future of Human Evolution: Autonomy
The RIAA/MPAA don't need to poison P2P networks. Nor do they need to use lawsuits and the threat of DMCA. The easiest, best way to stop illegal sharing of copyrighted materials is to provide a legal, reasonably priced electronic distribution alternative.
Really. Most users, given the choice, will pick the "honest" legal way to get their music and videos. Will there still be pirates? Of course, but you can never stop them and, heck, you're not losing money on them anyway. They wouldn't spend the money on the music.
Treat honest customers as honest, embrace new distribution methods. The problems go away. Think of the cost savings: they wouldn't have to buy any more senators.
tune, I may end up with somthing thats bland, repetitive and annoying.
And, pray tell, how am I supposed to know the difference?
The latest versions of limewire use hashes from a specification called HUGE that probably defeat this type of posioning attack. You can check out a recent interview with limewire team here. Go here if you want to download the code or check out the dev docs(Which are pretty outdated).
I love the smell of undergraduate sophistry in the morning...
The author of this paper seems to suffer from the common practice of those in a hurry to finish their term papers that if they somehow ignore the elephant in the room that disproves their point they might end up getting partial credit for impressing people with how well they can tap dance around the elephant. In this case the well-established practice of using a secure hash function as a self-verifying mechanism to prevent DoS attacks that try to flood a network with garbage files is the elephant.
In his FAQ regarding the paper, Mr. Chen correctly addresses the problem of a lack of centralized authority in using hash functions as distributed/P2P but apparently did not make more than a cursory examination of the subject or else he would have seen the various methods available for solving such a problem. I can only assume this is the case because reputation systems beyond simple moderation are not addressed and flow-constrained trust networks are never mentioned in this section.
As someone who seeks to pass off a "bad" file (this report) as a "good" file, perhaps sooner rather than later Mr. Chen will learn how the distributed moderation and trust system known as peer reputation works. Surely I am not the only one who finds it more than a little ironic that a paper by an author who claims that distributed moderation doesn't work is being submitted to a peer-reviewed journal in an attempt by the author to bootstrap his own reputation?
In particular, our analysis of the model leads to four potential strategies, which can be used in conjunction:
1. Randomly selecting and litigating against users engaging in piracy
2. Creating fake users that carry (incorrectly named or damaged files)
3. Broadcasting fake queries in order to degrade network performance
4. Selectively targeting litigation against the small percentage of users that carry the majority of the files
This mostly summarizes the war on drugs and the government's strategy against alcohol prohibition in the 1920's. Neither worked and the countermeasures are simple and straight forward.
A "directed" web of trust, objective quality measurement, and knowledge compartimentalization defeat the above strategy. The countermeasure of creating large numbers of mutally trusting attackers doesn't work when trust "flow" is taken into account. The keys to such a system are:
1) trust is assymetric
2) nodes define and change who they trust based on their own assessments
3) Nodes protect their knowledge of the web of trust
To see how this works, consider the cops and the drug dealers. The fact that the cops all trust each other does not result in the drug dealers trusting them. When a dealer is compromised, no matter how high up the chain it goes, trust shifts to rivals. Even when a kingpin falls, lines of trust will still exist that aren't compromised.
Drug dealing is not as popular as file sharing, is substantially more damaging to peoples lives and society, and has motivated levels of funding that are not matchable by publicly traded firms (who must demonstrate at least mid-range ROI). Despite all of these advantages, the war on drugs has been a dismal failure. The bottom line is that the internet makes distribution of content a commidity, where it was formerly a task of enormous complexity and value add. Economics will determine the rest, unless the US adopts and maintains a totalitarian government.