Post by stanlyy on Mar 3, 2023 0:59:37 GMT -6
It is natural to ask whether our techniques could be also fruitful for other permissionless blockchains. In our solution we focus on the specific mechanism used in Bitcoin to add illicit content in the Bitcoin blockchain (i.e., OP_RETURN and coinbase transactions). Our solution is specific to these mechanisms that permit to keep separate the UTXO database from data to be removed. In order to apply our technique to a different blockchain one needs to figure out how illicit data can be encoded in this blockchain, and if those mechanisms permit to separate the potentially illegal contents to be removed from the actual state of the blockchain (e.g., the equivalent of the UTXO database). Moreover, even in case it is possible to somehow apply our technique, it is extremely relevant to check if the update would cause a hard or a soft fork in the blockchain. Therefore, a successful application of our technique strongly depends on the inner details of the target blockchain. Another point to take into account is that in Bitcoin a new block is created each 10 minutes. Therefore, it is possible to exploit this time window to redact on the fly some transactions containing the OP_RETURN mechanism. In this scenario, once a node receive a data output transaction t , if t contains some illicit content (e.g., t contains some specific keywords), the node can decide to redact directly t without writing the illicit content in the storage.