For nearly a year, AOS, honored as the infrastructure project in the field of blockchain privacy, has garnered a lot of support and attention in the industry with its actions and results. Recently, AOS disclosed once again that there would be a major upgrade technically to better realize protection for privacy.

Undeniably, the transparency and immutability of blockchain technology contribute enormously to the realization of fairness and impartiality from a technical perspective. However, with the popularity of blockchain applications, more and more users and industries start to get involved, and at the same time, some sensitive business models and private exchange needs are not applicable to openness and transparency.

Industrial needs of blockchain plus privacy give birth to the first generation of privacy anonymous coins such as Monero, Zcash and Dash. This generation of anonymous coins all adopt UTXO model and POW mining mechanism. At the technical realization level, these anonymous coins universally adopt single ring signature, single confidential transaction and single zero-knowledge proof technology, which confines the application of the project. In the early stage of blockchain development, the industry’s need for privacy application only stayed on the level of payment and transfer and the technology back then was enough to meet the single demand.

With the continued expansion of the industry, the market’s need for technology seems more rigorous. Such backward driving force allows blockchain technology to iterate and develop rapidly. Requirements for privacy and anonymity are no longer confined to the single level of transfer and payment. A business ecosystem centering on smart contract needs more diverse privacy technical support.

AOS takes the lead of privacy technology in the smart contract era

In order to contain smart contract technology, AOS discards UTXO model and adopts Account model. Such flexible model allows AOS public chain to contain smart contract and privacy technology at the same time.

In the realization of privacy technology, AOS upgrades ElGamal encryption algorithm, which not only inherits the properties of safety and homomorphic encryption of the original ElGamal encryption algorithm, but also connects seamlessly to zero-knowledge proof system BulletProof. This will help AOS realize privacy under account model. The property of homomorphic encryption realizes the privacy of transaction amount and zero-knowledge proof ensures the correctness of transaction.

A plan based on the account model has its natural advantage: easy to understand, able to support smart contract, the payee able to verify payment without scanning the entire network, etc. However, there are some natural drawbacks. For example, the payer and the payee of each transaction are definite, and only the transaction amount is hidden and protected.

In terms of how to hide the payer and the payee, AOS has its superb coping style, meaning adding ring signature mechanism in the public chain technology, which is one of the priorities in this technical upgrade. The ring signature of AOS is expressed through building a coin mixing pool. When users want to start privacy and anonymous transfer, they will first pump the transferred assets into the coin mixing pool. Later, the assets will flow into the transfer-out address.

Case in point. On AOS chain, if A wants to send 100 privacy assets to B, then the 100 privacy assets will enter into the coin mixing pool first. At the same time, several assets of the same type and the same amount would enter into the pool and be mixed up. When the assets are transferred out, several assets of the same amount would also be transferred out and sent to different places for untraceable purpose. Besides, the ring signature will integrate with zero-knowledge proof to increase the variety of the batching processing of signature.

The adding of ring signature technology will allow AOS on-chain privacy to upgrade further. Users sending privacy assets with AOS can’t be traced, and the upgraded AOS anonymous plan will be done with the combination of ring signature, homomorphic encryption and zero-knowledge proof. Such a plan will be a brand-new one. It is not a ring signature plan of Monero 1.0 (known sending amount), not a Monero’s existing ring confidential transaction (unable to support account model and smart contract), and not a ZCash complete zero-knowledge proof plan (high energy consumption and low efficiency). After the upgrade, AOS will fully defeat Monero and ZCash in usability, anonymity, efficiency and other aspects.

Such upgrade of privacy technology will not only stay on the transfer level, the privacy data transfer at later stage and DAPP application. It will also be correspondingly upgraded. At that time, both user payment and large-scale commercial application will realize absolute protection for privacy and AOS will fully deserve the title of “the best public chain to support privacy in the world”.