Congratulations to the OpenBazaar team for their hard work and on their recent release! I firmly believe that global, decentralized, anonymous marketplaces will liberate millions. Whether it loosens the grip of a despotic state, or breaks the monopoly of a private company, OpenBazaar will help many, many people. For this reason I consider OpenBazaar’s work incredibly important, and therefore important to implement correctly. Unfortunately, the first production OpenBazaar release is conspicuously missing anonymity. Lack of anonymity severely hampers OpenBazaar’s ability to do good. Due to lack of information, I was under the mistaken impression that OpenBazaar stopped prioritizing anonymity. Recently, however, I was happy to read their recent blog post. The post enumerates five key limitations of OpenBazaar’s initial release. They address my two key concerns and three other important concerns I had not considered. Most importantly for me, they acknowledge the importance of anonymity for OpenBazaar. While I was overall encouraged, I was a bit disappointed to see IPFS favored over a project I’ve recently become passionate about: Freenet. Freenet has been battle-tested for 15 years and directly addresses three of the five limitations of OpenBazaar, and indirectly supports a robust solution for a fourth. On the other hand, IPFS is young and only addresses one of the five issues. Though IPFS is experimenting with integrating third party anonymization solutions, that only addresses two of five. Even if/when these changes are completed, I believe Freenet is a superior solution even for the two. These two are anonymity and offline storage, something Freenet is designed to do from the ground up. Freenet allows users to anonymously publish and receive pieces of static data, which fits well with OpenBazaar’s model.
Offline Stores
The OpenBazaar post correctly recognizes that many users may not want to run OpenBazaar’s server at all times. Currently, if a user turns off their OpenBazaar server their store becomes inaccessible. This problem is doubly important because I want OpenBazaar to help people worldwide, which must include people without reliable internet access. Freenet directly solves this by not storing data on the computer which publishes it. Using Freenet’s basic data insertion, OpenBazaar users could anonymously publish contracts which could be accessed even after the user went offline. When data is inserted into Freenet, it is stored on other computers according to a derived routing key. When that data is accessed, it becomes replicated across additional computers in accordance with its popularity. For this reason, data on Freenet cannot be DDoSed by repeatedly querying it. Contrast this with OpenBazaar’s current model, where identifying the correct computer to DDoS is facilitated by the network, and the data is not replicated elsewhere. IPFS does satisfactorily solve this issue, but it is still a relatively young project.
On the other hand, Freenet simultaneously solves multiple problems today, with over a decade of testing.
Anonymity
As I alluded to in the previous section, on Freenet, computers and IP addresses have nothing to do with the content they store, anonymity is built in. Freenet further improves anonymity by dividing and encrypting all data, limiting knowledge that other nodes may have about the data you are inserting or requesting. There exist (statistical) caveats to this, Freenet’s default behavior obfuscates data insertion and access quite effectively. More importantly, Freenet provides a mechanism for gaining stronger anonymity by only connecting to trusted friend nodes. By doing this, you further increase the difficulty of analyzing your traffic. The larger your network of trusted friends is, the better you are protected. In this way, privacy can scale with one’s desire for increased privacy. Freenet is also exploring a tunneling concept to provide yet another layer of protection. All said, Freenet provides adequate anonymity by default, and provides the ability to improve anonymity as needed by adding trusted friends. IPFS on the other hand does not support anonymity natively, and any support will be experimental for the foreseeable future. Further, Freenet is designed to simultaneously support anonymity and offline caching, and the two properties compliment each other. This is opposed to the way IPFS would interact with privacy layered on top. Consider that Torrenting via Tor is discouraged due to traffic requirements. Instead, popularity of a piece of data on Freenet makes its retrieval more efficient as it is replicated in more places.
Reputation
Freenet includes a third feature OpenBazaar requires in the form of an official plugin developed directly by the Freenet Project Inc. WebOfTrust is a plugin for Freenet that provides spam-resistant data publishing on the Freenet network. It accomplishes this by defining the concepts of identities, and trust between identities. An identity (optionally) lists other identities which it trusts or distrusts, and by how much. By considering all known identities, this produces a directed, weighted graph with identities as vertices, and trust relationships as edges. By traversing this graph from one identity to another, WebOfTrust calculates how much that identity trusts another. OpenBazaar can utilize this framework by setting trust based on their seller reviews. If Alice is scammed by Eve, and Alice writes a negative review, Alice’s WebOfTrust identity would indicate distrust to Eve’s identity. If Bob has positive or neutral trust to Alice, Bob would then transitively distrust Eve. Each trust relationship also may have arbitrary data attached to it, allowing a proof to be included. Furthermore, if Bob determines that Alice’s bad review of Eve is fraudulent (lacking a proof), Bob may choose to lower his trust of Alice in response. Those who trust Bob would then have lower trust of Alice, and potentially higher trust of Eve.
Search
Finally, Search can also be facilitated by the above Reputation algorithm. If a user is well trusted, and they claim a contract belongs to a particular keyword, that will be considered “correct”. If a user is not well trusted, the keyword may be ignored when searching. Conflicting keywords would be resolved by some weighted summing and a threshold value, and spamming keywords could be discouraged by automatically distrusting identities which do this (such spam would be identified manually by the user). In fact, prevention of spam like this is the core purpose of Freenet’s WebOfTrust!
Because Freenet adeptly addresses three of five significant concerns of OpenBazaar, I argue that the OpenBazaar team ought to carefully evaluate Freenet as a potential backend platform for OpenBazaar. I have a decent working knowledge of Freenet and am more than happy to lend my efforts to the OpenBazaar project (though there are far more knowledgable individuals in the Freenet project). I did not seriously pursue this earlier because I was under the impression OpenBazaar was de-prioritizing anonymity, but I am happy to find that I was very mistaken. This document will undergo further revisions, but I am going to publish it as soon as possible.
I intend to follow this post with a more concrete proposal for a Freenet backend. I also welcome any questions, comments, or corrections for this article.
P.S. Thank you to the redditors that brought the OpenBazaar blog post to my attention, and encouraged me to publish my thoughts. (And thank you to the OpenBazaar team for making the world a better place)
The original OpenBazaar blog post: Current Limitations of the OpenBazaar Software
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