Building the “VISA of Web3”: TOPOS, a Web3.0 Encrypted Payment and Clearing System Built on PlatON, Is Officially Released

PlatON Network
7 min readApr 18


Recently, on the “Global Payment in Web3” forum in “Hong Kong Web3 Festival 2023”, Sun Lilin, the founder of PlatON, delivered the opening speech titled TOPOS: Tokenized Open Payment Operating System, and officially released TOPOS, a Web3.0 encrypted payment and clearing system built on PlatON.

Payment systems have evolved along with changes in the carriers of currency value and the methods of credential authentication. In the broader context of today’s Web3 development, cryptocurrencies technically empower the complete unification of information flow and capital flow. However, the current payment architecture can only handle the clearing rules with peer-to-peer transfers at the core in the early stage, and there is not a set of clearing and settlement standards that can cope with various complex payment scenarios involving multiple parties.

“We believe that in the Web3 world with blockchain as the underlying platform, the unification of information flow and capital flow, as well as non-custodial solutions, will become reality someday. Currently, centralized exchanges (CEXs) are actively exploring the payment of cryptocurrencies as a currency. This approach bears more resemblance to the centralized wallet logic of Alipay, which is relatively mature and offers valuable lessons in terms of cost reduction and efficiency improvement. However, this method also undermines two fundamental characteristics of cryptocurrencies: the non-custodial and the unification of information flow and capital flow. Yet based on cross-chain transaction execution, there is not a set of on-chain clearing rules that can accommodate the interests distribution among multiple payment parties and complex payment scenarios,” said Sun Lulin. “Therefore, we believe that a blockchain-based clearing and settlement system standard will inevitably emerge in the future.” This is precisely the opportunity that gave birth to TOPOS.

What is TOPOS?

TOPOS stands for “Tokenized Open Payment Operating System”.Built on blockchain technology, TOPOS adheres to the OPEN LOOP multi-party architecture. Anyone can utilize the blockchain capabilities provided by TOPOS to assemble the final payment services within this ecosystem. Merchants and users can hold Web3 assets without the need for a custodian, relying instead on acquirers, wallet institutions, and developers of Tokenized Money payment scenario standards to complete payments and exchange value. Similar to the VISA/MASTERCARD system, parties in payment take on different roles to complete their tasks and earn profits.

TOPOS is referred to as an operating system because it doesn’t directly provide payment services, similar to VISA. Its primary function is to establish the standards for operating the underlying blockchain. This payment standard, which is based on Tokenized Money, has the potential to revolutionize the current payment system in terms of compliance, security, and ecosystem value.

The Payment Core of TOPOS: Tokenized Money

At the core of TOPOS is Tokenized Money, and the entire payment lifecycle of Tokenized Money is referred to as encrypted payment. The underlying system of TOPOS offers corresponding components and contracts for encrypted payment. Currently, it has completed the technical verification of using ZK Proof as an authorization certificate and developed products concerning the usage of homomorphic encryption (HE) to encapsulate one-time payment certificates for one-dimensional code payment. Furthermore, it has developed contracts for implementing secured transactions, QR code transactions, and other push payment scenarios based on signatures. In the near future, TOPOS will open up these components to acquirers, e-commerce platforms, wallet partners, etc.

Tokenized Money consists of three layers:

The most essential layer is the locked value. Tokenized Money is not an unlimited authorization certificate and thus has a definite payment value for a single execution action. This value can be represented by a stablecoin, CBDC, BTC, ETH, or any other consensus-based asset that can be settled.

Outside the locked value is the payment logic, which includes settlement conditions, clearing rules, time constraints, scenario constraints, etc. Every payment comes with a corresponding transaction logic that can effectively prevent the uncontrolled circulation of assets to be settled and provide payment constraints at the protocol level. This helps acquirers, wallet institutions, and others manage risks effectively.

The outermost layer is the authorization mechanism, which serves as the cornerstone of payment security. In the Web3 world, cryptography is the primary safeguard for authorization mechanisms. Methods such as Zero-knowledge (ZK) Proof, HE, and digital signatures can provide the most versatile solution to various needs of accepting parties for authorization in various scenarios.

With this three-layer architecture, ultimately, users in Web3 could be able to self-mint “money” that can transfer value in a secure and controllable manner.

Compliance Security and the TOPOS Economic Model

As a protocol-layer service, TOPOS mainly relies on cryptographic components and smart contracts. Therefore, from the perspective of compliance, TOPOS has separated the issuance of off-chain assets on the chain, encrypted payment-related contracts, and value exchange-related contracts into different components. Under such an architecture, parties can engage in a specific component independently, which helps them expand business in a way compliant to their jurisdictions.

Ensuring the security of the entire system requires more than just encrypted payment. A large number of cryptographic components and basic services are needed to make the payment ecosystem work. With the technical support of the LatticeX Foundation, TOPOS employs Multi-Party Computation (MPC) in the design of settlement currency issuance, which helps the issuer define internal issuance approval processes while meeting the needs of API integration. In terms of contract design, TOPOS not only features compatibility with mainstream implementations such as ERC20, EIP712, EIP1155, EIP2612, and EIP3009, but also introduces the function of contract auditing prior to issuance, which helps issuers better manage reserve assets and facilitates asset auditing.

It is worth noting that TOPOS, through an open payment ecosystem, can slash the high cross-border payment fees by at least 60%. In the cross-border payment process of VISA/MASTERCARD, merchants bear high fees, and users face hidden costs during currency exchange. The overall payment cost could consume over 5% of the transaction amount. The distribution of these revenues heavily favors card organizations, which precisely explains their highest valuations in the global payment ecosystem. By contrast, with the open architecture, TOPOS will only take up a small portion of the revenue, part of which is allocated to the creator of the Tokenized Money protocol while another is paid as gas to the underlying PlatON blockchain platform. In some scenarios, such fees, overall negligible, can also be paid by the acquirer or wallet. The majority of the revenue will be distributed to the payment service providers, i.e. the acquirers and wallet institutions, so that they can gain more benefits from the ecosystem for serving merchants and users.

“In the future of Web3, we believe that as more and more assets become currencies that can be settled based on consensus, there will be increasing currencies for settlement in the ecosystem. The clearing and settlement of these currencies will be more like today’s cross-border payments. So predictably, cross-border payments will take up a significantly greater proportion in the Web3 world, possibly from the current level of 20% to 80%. As a result, the TOPOS economic model, under such a development trend, could save considerable costs overall and distribute more revenue to acquirers and wallet service providers,” said Sun Lilin.

Out of Many, One

Over the years, instead of blindly following the herd, PlatON has persistently engaged in the cultivation of underlying technology. The official debut of the payment and clearing infrastructure TOPOS represents a perfect transition in PlatON’s focus from underlying technology to upper-level business. Committed to becoming the VISA of a decentralized federal system in the Web3 world, TOPOS will consistently draw global developers, card issuers, acquirers, wallets, and other third-party specialized service institutions into the construction of a multilateral payment and clearing architecture based on multi-party consensus under the global regulatory compliance framework.

What is the “VISA of Web3” and what is the next generation of global clearing and payment infrastructure? If we were to summarize the core concept of TOPOS in one sentence, as Sun Lilin said, we could refer to the motto on the United States’ emblem and answer, “Out Of many, One.”

Only the win-win ecosystem under the global multilateral framework has sustainable value. We look forward to the future and development of TOPOS!



PlatON Network

PlatON — An Infrastructure for Privacy-Preserving Computation and Distributed Economies.