Roxe Chain Technical White Paper

© 2020 Roxe Chain Foundation 

1. Preface

“Roxe Chain” has been under development by the Roxe Chain Foundation (“The Foundation”) since early 2019 and, as of August 2020, we have completed building the infrastructure for the first two of the three stages in the ‘strategic plan’ outlined below. We are developing the core ecosystem, and are currently building the technology for the third phase. 

Our intention in developing the Roxe Chain is to use blockchain technology to create a DeFi infrastructure that solves the myriad of problems caused by the fragmentation of global financial markets.

Despite the development of a large number of chains, the world still lacks a chain dedicated to Decentralized Finance (DeFi). 

We strongly believe that the outdated global payments and clearing value transfer system will achieve step-change improvements with the application of blockchain technology. 

Roxe Chain, a hybrid chain, was created to serve as the DeFi infrastructure that will generate the next big leap forward in finance. 

 

2. Background Overview

Thanks to the efforts of the World Trade Organization (WTO) and the major economies after World War II, consumer goods have achieved free circulation worldwide, but the global circulation of financial assets has been hindered by centralized organizations. For example, buying Apple’s stock is more complicated than buying an iPhone. Today, financial assets circulate slowly relative to their potential, due to the fragmentation of the global value network and the obsolescence, inefficiency, and isolation of the international settlement infrastructure are key reasons for the poor circulation of financial assets.  

Roxe Chain is a hybrid chain for value exchange that enables payment settlement via a DeFi infrastructure. The fundamental approach is to send and receive currencies and digital assets faster using blockchain technology. We believe that a completely decentralized full-asset clearing and settlement network is essential to achieve the full potential of cryptocurrencies. Such a network will eliminate centralized intermediaries and barriers, and unlock benefits for society at large – generating tremendous value for stakeholders. Global mainstream asset tokenization enables any person or institution to circulate their assets on-chain at any time and from any location. We will make historic improvements by establishing an asset circulation network that is as efficient as information networks are today.

Roxe Chain is purpose-built to power 3rd-party cross-border payment, settlement, and other value transfer applications. Its core objective is to establish a simple, and efficient value transfer mechanism that will scale across asset classes. The design is elegantly simple, ensuring relatively low interaction with its nodes’ business and accounting systems. At present, there are already thousands of crypto trading platforms, wallets, and industry solutions available globally, and there are likely to be many more in the future. These platforms generally have independent and exclusive economic and technical systems, inhibiting value from flowing freely. Roxe Chain Foundation intends to bridge the divide between technology and value to achieve an open connection to existing value systems at a low cost. 

Roxe Chain is developed by The Foundation’s core development team and is the hub of the entire value circulation network. The Foundation is committed to collaborating with external developers and will open the source code of Roxe Chain to like-minded world-class developers to accelerate R & D progress. 

 

3. Vision and Mission

Enable value to move freely, globally, and instantaneously. 

Roxe Foundation’s mission is to build an infrastructure upon which other organizations can develop global payment, settlement, and other value transfer networks across asset classes. Online asset circulation via Roxe’s infrastructure can extend beyond digital assets and payments to virtually any asset that can be tokenized with blockchain technology.  Using the Roxe Chain, any organization can develop applications and freely choose its role to participate in minting, redemption, clearing, settlement, and/or leveraging these services for transactions.

Roxe is building a value circulation system and financial infrastructure that will connect more than 160 countries and billions of people in a compliant manner. In doing so:

1. Roxe is built to understand, acknowledge, and work within the logic of value storage of different assets, by country and region.
2. Roxe serves as a value circulation channel for each asset without replacing any asset.
3. Roxe Chain is built to enable 3rd Parties to create and deliver instant global clearing and settlement across a wide range of digital assets and fiat currencies.

4. Opportunity

We believe that the market needs the Roxe Chain now, and we are partnering with individuals and entities who share these same ideals: 

• Globally distributed, fragmented value silos can collectively create and capture more value together, connected via a network, than alone. The world needs value to flow as easily as information does;
• Business globalization will increase by reducing friction with more efficient financial infrastructure; a high-functioning value circulation system can eliminate costly market friction;
• Time is money. Liquidity enables faster execution;
• Everyone should be able to enjoy the benefits of globalization; and
• Every participant can capture value via the Roxe ecosystem

 

5. Network node types

Supernode

21 “Supernodes” that join the network will provide computing power and bandwidth support to ensure efficient operations for the entire Roxe Chain network. The supernode model is extremely valuable to global clearing and settlement, as it enables short block generation time, higher efficiency, and anti-fork attributes. Any organization can apply to be a supernode. Subsequently, each supernode will benefit from continued Roxe Chain ecosystem development.

Candidate node

In addition to supernodes, Roxe Chain anticipates having hundreds of candidate nodes. If a supernode triggers a downgrade condition (is unable to perform its obligations as a supernode on time), the top-ranked candidate node, determined by community voting, will step in. The upgraded candidate nodes will take over all the rights and interests of the downgraded supernodes.

Cross-chain gateway

Banks, exchanges, and other platforms with cross-chain settlement capabilities can apply to become settlement gateways, and users of cross-chain gateways can perform cross-currency settlement of digital currencies and fiat currencies via the cross-chain gateway. Cross-chain nodes provide Roxe Chain with accessibility to virtually any asset class. Cross-chain gateways can potentially increase capital utilization, reduce FX conversion costs, and attract more customers with unique, differentiated services.

 

6. Technical Goals

In addition to the functions outlined above, Roxe Chain is designed to achieve critical technical capabilities relative to alternatives, including:

1. Faster transfer speed
2. Support transfer of more types of assets
3. More transparency via an implicit audit trail
4. Higher security
5. More stable operation

 

7. High Concurrency

Roxe Chain is a blockchain system architecture based on Graphene technology, which is an open-source blockchain technology written primarily in C++. Graphene technology meets the needs of vertical decentralized applications and horizontal expansion through a plug-in structure, and is based on a BFT-DPoS (Byzantine Fault Tolerance-Delegated Proof of Stake) consensus plugin and sharding. 

Roxe Chain solves the problems of low performance, poor security, difficult development, and difficult cross-chain communication in existing blockchain applications, and achieves the performance potential of distributed applications.

 

8. Consensus Algorithm 

aBFT-DPoS consensus

Roxe Chain is designed to achieve confirmation of irreversibility within one second using the aBFT-DPoS (asynchronous Byzantine Fault Tolerance-Delegated Proof of Stake) consensus to achieve faster irreversibility. By adding a Byzantine Fault Tolerance algorithm to the traditional DPoS algorithm, all block producers must sign all blocks to ensure no block producer is at the same timestamp or sign two blocks on the same block height at the same time. A block that is signed by two-thirds of the block producers is considered irreversible. Any Byzantine block producer who wants to sign two blocks at the same timestamp or on the same block height will leave cryptographic evidence. In this mode, an irreversible consensus can be reached within one second. 

The asynchronous assumption-based aBFT algorithm is not dependent upon the synchronization-based assumptions practical Byzantine Fault-Tolerant algorithm PBFT,  improving performance, making it more practical.

Transaction as Proof of Stake (TaPoS)

Unlike the underlying data structure of other blockchains, in which the latter block contains the hash of the previous block to form the blockchain, TaPos (Transaction as Proof of Stake) requires that all transactions must contain the hash of the most recent block header. This hash has two purposes:

1. Prevent replay of transactions on the blockchain fork, and these transactions do not include reference blocks;
2. Notify the blockchain network that a user and its stake are on a specific fork.

Over time, all users can directly confirm the blockchain, which makes it difficult for counterfeit chains to forge because counterfeit chains cannot transfer transactions from legitimate chains, thus preventing the verifier from maliciously operating on other chains.

 

9. High Throughput

Graphene technology

The bottom layer of Roxe Chain is based on Graphene technology. It is a blockchain tool kit. At present, the Graphene blockchain library has been adopted by many well-known blockchain projects.

Graphene has the characteristics of fast transfer speed and high throughput. It is stable, powerful, complete, and easy to operate.

Region technology

Region technology is the same as sharding technology, which is a parallel computing technology. Region technology does not run in parallel within the application. Instead, it extends the network through the cross-chain concurrency technology of the sharding chain, and through the asynchronous communication to separate the authentication and execution processes.

All transactions are separated by region numbers to form a partition chain. Each partition chain is single-threaded, and multiple partition chains can be run concurrently on a node to fully utilize all the performance of each node. The performance upper limit of a single node can be expanded through clustering to achieve a high-throughput and highly scalable underlying architecture.

10. High Security

Supernode and transparent forging

The tradeoff between transaction speed and data security on the blockchain has been a problem since the early stages of digital assets. If block confirmation speed is too fast, this can cause double payment (double-spending problem), resulting in insecure blockchain transaction data. Through the transparent forging mechanism, the nodes of the entire network confirm the bookkeeper (supernode) in advance, saving the time of searching for miners, thereby increasing the speed of block transactions and ensuring the security of transactions.

Roxe Chain plans to utilize 21 supernodes. The block generation orders for supernodes and the auditing orders for all network transactions are all automatically calculated by the system and irregularly changed so that they can be efficiently upgraded while preventing cheating and avoiding hard forks.

Ownership model to defeat DoS attacks

DoS attacks (Denial-of-service attack) occurs when malicious attackers send a large volume of spam traffic to the network, which causes the network to be paralyzed and unable to process legitimate requests. At present, some networks have been vulnerable to DoS attacks. In comparison, Roxe Chain is less vulnerable to DoS attacks due to the ownership model. 

Network bandwidth, storage space, and computing power will be allocated in proportion to the number of platform tokens held by users. Therefore, malicious attackers have to consume the corresponding proportion of network resources held by platform tokens without disrupting the entire network. Even if many malicious agents try to create junk congestion for several large-scale network applications, this approach will ensure the bandwidth reliability and computing power of small-scale startup investment projects on the network.

Node acceptance mechanism

Roxe Chain will use a hybrid network, and currently, there are no plans to adopt a fully open network approach. Acceptance mechanisms will be implemented for supernodes, candidate nodes, and cross-chain gateways. Nodes must comply with the mandatory security control standards of the Roxe protocol. Only those who pass the screening can access and enable the node. At the same time, the node also needs to set an IP whitelist and visit policy to limit the direction and path of communication within the network to ensure maximum security within the chain.

 

11. High Scalability

Plug-in

Roxe Chain uses the Graphene code base as its foundational architecture and implements a flexible modular plug-in mechanism. A layer of template classes is inserted between the abstract plug-in class and the specific function class to decouple the inter-plugin dependent calls from the specific function class. This is conducive to the cohesion of plug-in functions and the expansion of new plug-ins.

The plug-in-designed Roxe Chain is highly decoupled, and the function modules can be independently developed and combined freely as needed. At the same time, a variety of functional middleware plug-ins and components based on Roxe Chain will be launched in succession.

Smart Contract

Roxe Chain smart contract uses Web Assembly (WASM). Web Assembly is an emerging and high-performance virtual machine. It has an LLVM compilation backend and is compatible with all programs written in high-level languages ​​such as C, C ++, and Java. The learning cost for developers is low. 

At the same time, WASM byte code is flexible, which can be compiled into machine code for execution or can be directly executed using an interpreter, with both compatibility and performance. The advantage of compilation execution is that its execution speed is fast. However, the disadvantage is that every time the smart contract is updated, the witness’ server must recompile to generate binary machine code, which is generally used for deterministic smart contracts that are executed multiple times. The interpretation and execution are just the opposite in that no pre-compilation is required, but the execution speed is much lower than that of compilation and execution. It is generally used for debugging or temporary smart contracts.

Independent architecture of virtual machine

Roxe Chain is built with a virtual machine independent architecture and supports multiple virtual machine sandbox operations. Any virtual machine that meets the conditions of performance, certainty, correctness, and sandboxing can be connected. In addition to Web Assembly, it also supports the Ethereum Virtual Machine (EVM) that runs on existing Ethereum contracts.

Based on the EVM, any smart contracts on Ethereum can run on the Roxe Chain, with minor modifications. Also, projects on Ethereum can be smoothly migrated to the Roxe Chain.

 

12. Account System

Easy-to-use account system

With Accounts, a readable account system, 2 to 32 human-readable characters can be used to create an account. The name is chosen by the account creator. The account creator must set aside RAM space for storing new accounts until the newly created account pledges the token to obtain RAM space.

Permission management based on roles

Roxe Chain provides an Assertion permission management system that allows accounts to exercise both highly granular and high-level control. Identity authentication and permission management are standardized and isolated from the application business logic so that permissions can be managed without impacting adjacent systems while providing performance optimization capabilities.

Roxe Chain also supports multi-account control, which provides account security and reduces hacker attack risk. Through named message processing groups, it is even allowed to define what types of secret keys or accounts can send a specific message type to another account. Named message processing groups can be referenced when other accounts configure permission levels. Mapping can be completed between permission levels and message processing groups: Assign a message processing group to a certain permission level, or conversely, define various message processing groups at certain permission levels.

The default permission groups are Owner and Active. Owner can do anything and is generally used for cold backup. If Active permission is lost, Owner permission can be used to restore that permission. Active permissions can do everything except modify the Owner. Routine business can be handled with Active permission. All other permission groups are also derived from Active permissions.

Secret Key Recovery

Roxe Chain provides a secret key recovery mechanism if an account balance becomes zero after the private key is stolen or the password is forgotten.

On other chains, when the secret key is lost, the entire account is also lost. However, the secret key recovery mechanism based on Roxe Chain can recover the key using any Owner permission key and a designated partner within 30 days. In this case, the partner cannot recover the key without the assistance of the owner, and the partner will not participate in any daily transaction.

Roxe Chain protects account assets through a safe combination of accounts, key-pairs, wallets, and authorities & permissions.

 

13 Cross-chain

Cross-chain communication

Roxe Chain simplifies the generation of Proof of Action existence and Proof of Action sequence to promote cross-chain interaction on blockchains. These proofs are combined with the application architecture designed around message passing, which hides the details of cross-chain communication and verification proofs from the application developers. Developers are only presented with high-level abstractions. 

Merkle proof

Roxe Chain uses the “Merkle proof” as Proof of Action verification to achieve blockchain interaction. The Merkle tree is also called a hash tree, for which any changes in the underlying data will be passed to its parent node to the root of the tree. The use of Merkle Proof for Light Client Verification (LCV) is to produce a relatively lightweight proof of transaction existence; this can verify the proof by tracking a lightweight data set, that is to prove a specific transaction is included in a specific block, and this block is included in the history of the specific blockchain that has been verified.

SegWit

SegWit (Segregated Witness) means that, after the irreversible inclusion of a transaction in the blockchain, the signature of the transaction is no longer relevant. Once the transaction is tamper-proof, the signature data can be cut off, and everyone else can reach the current state. Since signature data occupies a large part of most transactions, SegWit can significantly reduce disk usage and synchronization time.

The same concept can be used in Merkle Proof in cross-chain communication. Once a proof is accepted and irreversibly recorded on the blockchain, the 2kb file of the sha256 hash, used as a proof is no longer needed to reach the correct blockchain status. 

Cross-chain asset mapping

Roxe Chain uses both sub-chain and side-chain technologies to achieve cross-chain interaction, transactions, and asset mapping. It lifts the technical limitations of isolation between main chains and gradually realizes truly decentralized mapping technology.

Sub-chains are logically formed by the main chain. These sub-chains share supernode computing resources and interact through a cross-chain mechanism. Each adaptor sub-chain is connected by a cross-chain main chain, and there is no trust relationship between each sub-chain.  Rather,  trust is transmitted through the main chain. The adaptor chain and main chain interact according to the protocol to achieve trust transfer and transaction transfer.

Like a hard fork, the sidechain is an independent chain directly initiated by Roxe Chain source code. The sidechain has its own committee, computing resources, and tokens. The sidechain anchors a token on a certain original chain, verifying data from other blockchains. It enables Roxe Tokens to be moved between different blockchains, building a new and open platform, such as creating micropayment channels under the main chain, etc.

Roxe Chain will continue to improve the application of cross-chain technology on different platforms, use decentralized methods to provide custody mapping for more assets as well as a more secure, reliable, and trusted infrastructure for asset custody.

 

14. Special Network

Closed smart contract

To maintain business efficiency and speed while ensuring the purity and security of Roxe Chain Foundation’s third party networks, Roxe Chain does not support open smart contracts, and all basic services are supported by the accepted nodes and chain modules.

Based on the ecosystem development plan and the Roxe Chain business requirements, corresponding smart contracts will be released to the Roxe Chain only after they have been approved by the Foundation’s management committee, and all contracts on the chain should undergo security audits.

Trust mechanism

In the Roxe Chain, settlement nodes follow the Roxe Protocol to audit the asset mapping request. Meanwhile, Roxe not only provides technical capabilities, but it also contains a series of authorization mechanisms to ensure all business of authorized nodes will be periodically reviewed. If nodes fail the review, Roxe Chain will initiate a credit adjustment as an incentive mechanism for nodes.

Distributed Depository Mechanism

The distributed depository mechanism is the basic service of Roxe Chain. All mapped currencies will be escrowed into the distributed escrowed-asset pool and managed by the corresponding settlement node. It accepts triple layers of supervision from other nodes, Roxe Chain, and audit institutions. 

Unified KYC and Fast Verification

Each node will have KYC (Know Your Customer) requirements, with requirements varying based on the region. At the same time, Roxe Chain will also recognize the behavior of the same user in different nodes, share security information among nodes while adhering to relevant privacy considerations, and maintain blacklists. Roxe Chain will also build a self-learning trading mode detection based on user behaviors, which can identify and prevent suspicious fraudulent activities.

 

15. RoxeSwap

Roxeswap Protocol

The Foundation uses the Roxeswap Protocol to manage complex asset networks and value transfer relationships.

Roxe Middleware

In addition to the Roxe protocol, Roxe Chain also provides nodes with secure Roxe middleware components to quickly access settlement nodes. Roxe middleware is a set of infrastructure components based on the Roxe Protocol, including the: asset registration component, rapid mapping component, hot and cold wallet component, smart contract component, security authorization component, node verification component, credit fast settlement component, asset access components, audit components, etc. The nodes can be used in combination according to the access form, method, and service content.

Roxe Chain can also be used as a storage infrastructure. The fast open ledger can realize such functions as low commission, high concurrent throughput, and fast transaction confirmation.

 

16. Clearing Protocol

XMoney Fast Clearing Protocol

The XMoney Protocol is a fast-clearing protocol on Roxe Chain.

Since nodes often provide clearing for the same user (i.e., user transfers between exchanges), to improve the efficiency of clearing between nodes and the speed of funds transfer between different nodes of the same customer, nodes with XMoney Protocol can accelerate the instant clearing of assets.

The XMoney Protocol has formulated various execution scenarios and specifications under fast clearing. At the same time, authorized nodes have priority clearing rights and fast pre-settlement privileges.

Executing the same settlement protocol helps regulate the settlement agreement between nodes, reducing the difficulty of communication between new nodes and existing nodes, thus making the settlement between nodes faster, clearer, and more standardized.

 

17. Roadmap

18. Roxe Cash (ROC)

ROC Economic Model

Roxe Cash (“ROC”) will be Roxe Chain’s digital encryption-secured token and will be a transferable representation of an attribute function specified in the Roxe Chain code/protocol. It is designed to play a primary role in the operation of the Roxe Chain  and to be used only as the primary utility token on the network. ROC is the ‘gas’ to run the Roxe Chain.

ROC will be a non-refundable, functional token that will be used as an exchange medium on Roxe Chain.

ROC will greatly strengthen the connectivity between networks, improve the effectiveness of interactions between scenarios, and ultimately accelerate the large-scale value flow.

The purpose of ROC is to provide a convenient and secure method of payment and settlement for participants on Roxe Chain.

 

19. Conclusion

Roxe Foundation’s mission is to build an infrastructure upon which others can develop a global payment settlement network. Online asset circulation via Roxe’s infrastructure can extend beyond digital assets and payments to virtually any asset that can be tokenized with blockchain technology.

 

Roxe Chain is designed from the ground up to serve as the foundation for 3rd party instant value transfer and settlement solutions. Roxe Chain’s high concurrency, throughput, and state-of-the-art security ensure that 3rd parties can build settlement and other value transfer networks with confidence.  

In summary, Roxe Chain Foundation has built Roxe Chain to enable financial value to move much faster at much lower cost anywhere across the globe.