The virtual world is full of threats; Sybil attacks make a sizeable chunk of it. Especially with the increasing implementation and usage of peer-to-peer networks, the network infrastructure lies more exposed to such attacks than ever. Cryptocurrencies also use a form of peer-to-peer network, which naturally puts them on the list as well. The magnitude of threat is now being countered by the development and implementation of anti-Sybil protocols.
Proof of Individuality is one of the protocols currently being developed to counter Sybil attacks. The term Sybil is based on a book by the same title where the lead character suffers from Multiple Personality Disorder. Similarly, in its digital form, Sybil Attacks usually spoof the computer reputation systems by forging the identity of peers connected to the network. This leads to a large number of fake peers that overloads the network to influence the decisions and output of the system.
According to a recent post on Bitnation’s blog, the Proof of Individuality protocol is influenced by Bryan Ford’s draft paper titled Pseudonym Parties: An Offline Foundation for Online Accountability. The paper suggests the use of offline events – gatherings across the world – to verify the individuality of the participants.
Now, can the same process be applied in the virtual world? The answer is yes; it can be implemented by using a simple everyday chat application like Google Hangouts or the latest Microsoft Holoportation for a more refined 3D capture system currently developed by Microsoft Research.
Every participant of the hangouts conference, held once every month can be assigned with a Proof of Individuality token minus identifiers that could reveal his identity. These Tokens can be linked to a private key, with an expiration date of one month. Once the active period is over, the token – a smart contract by itself – will automatically schedule another round of virtual conference. Once the conference ends, a new token will be automatically assigned to the participant.
By ensuring that that there is no connection between the previous token and the fresh one, anonymity of the users can be maintained. The Bitnation article goes on to mention the rewarding mechanism that can be incorporated into the system, a type of crypto token that can be transferred from one participant to another. By setting a minimum token requirement for each participant, the individuality of the participant can be further confirmed.
The Proof of individuality protocol as described above will be built using smart contracts over Ethereum protocol and it can be used to ensure that the individual connections/identity is not being spoofed by a third party with malicious intent. even though there is a chance of actual connection/system being hijacked, the probability of such an occurrence is negligible. Even in such an unlikely scenario, the number of systems that needs to be hijacked to make even a small dent in the whole network is very high, hence impractical.
However, the practicality of using this exciting anti-Sybil solution for all blockchain-based applications is yet to be tested.