When L2 rollups were first introduced to the crypto space as a scaling solution, many incorrectly assumed that confidentiality was baked into their base protocols. This is incorrect, however we believe that layer-2s such as zkSync deserve a privacy solution, as this is where crypto users make most of their daily transactions and are at the highest risks.
Without the use of confidential transactions, adversaries are able to track your on-chain activity and use it to extract value from your behavior.
Version 1.0 of Hush is a smart contract that users/contracts can send assets to, along with a signature detailing a recipient who holds the deposit claim. The assets (ETH) are held in a shared escrow that behaves like a black-box. Once deposited is sent to the shared escrow, only the signed recipient address will be able to withdraw the payment. After this process, the origin of the assets will be obfuscated.
However, there are other considerations to be made, such as time and value correlation attacks. If a depositor makes a deposit of a unique value, such as 0.1276 ETH, and quickly thereafter, a recipient withdraws the same amount, it can be asserted with relative certainty that the identity of both the depositor and recipient is the same.
To solve value correlation attacks, Hush utilizes default transaction sizes, such as 0.1, 1.0, and 10 ETH. This improves the anonymity set and greatly increases difficulty of correlation. Additionally, to solve time correlation attacks, Hush doesn’t push the transactions to their recipients immediately. Rather, they can be claimed at a later time.
The HUSH token plays an integral part in the Hush ecosystem, and is designed to support and facilitate the platform’s operations. It is trading on Mute.io, liquidity is locked, and the contract is renounced.
Holders of the HUSH token are entitled to earn a share of the fees generated by the platform. To use the Hush platform, users are charged service fees. These fees are dynamically set based on transaction size, and can vary from 0.25% to 0.50% of each shielded transaction. Fees are allocated to reward HUSH holders.
In addition, HUSH token holders have the ability to make proposals that dictate the operation of the platform, giving them a say in the future direction of the framework. Through this process, they can vote on important changes that affect them, such as transaction fees and the fee share rate. This democratic approach to decision-making ensures that the platform is constantly evolving to meet the needs of its users.