# Getting Started

## What is Rangers Protocol

Rangers Protocol is the backbone of a Web3 Engine for creating immersive Web3 applications. It minimizes the development difficulty for Web3 developers and maximizes the user experience of its Web3 applications. Rangers Protocol provides comprehensive infrastructures for efficient complex-app development, successful cross-chain and mass distribution, diverse in-app NFT and DeFi features, and more. Through its full EVM-compatibility, strategic industry partnerships and its curated all-in-one IDE, Rangers Protocol supports AAA and indie developers to succeed in the Web3 world.

## Introduction of Consensus Mechanism

Rangers Protocol consists of two core technologies — Rangers Mainnet and Rangers Connector. Rangers Mainnet includes the RPoS-based VRF+BLS consensus mechanism and is a high-performance, highly scalable chain that can support complex applications. Rangers Connector includes a consensus mechanism based on VRF+TSS and is responsible for completing the cross-chain services with various public chains.

VRF, or Verifiable Random Function, is an algorithm for generating random numbers. The advantage of using VRF is the relatively low power consumption. With the latest algorithms, verifying the legitimacy of VRF has been very fast, and it is an efficient consensus algorithm. In Rangers Protocol, the VRF algorithm is used to select candidate block packers and candidate block verification groups.

The BLS signature algorithm was proposed by three people from the Department of Computer Science at Stanford University: Dan Boneh, Ben Lynn, and Hovav Shacham. BLS’s main idea is to hash the message to be signed to a point on an elliptic curve and use the exchange property of the bilinear mapping E function to verify the signature without revealing the private key. The BLS signature algorithm is mainly used to aggregate each member’s signature in the verification group for the candidate block to generate the verification group signature.

TSS, or Threshold Signature Scheme, is a technology that changes the traditional 1:1 correspondence between the public and private keys to 1:N public and private keys proportion. The algorithm can be passed as long as t of the N private keys are used to sign the message independently. What differentiates it from multi-signature is that the latter occurs on the chain, while the threshold signature occurs off-chain, which can save the cost of calling operations on the chain multiple times.

Block Production Process

• VRF selects a proposal node from the proposal group and is responsible for generating blocks;

• The proposal node selects the verification group through VRF, and the proposal node sends the block to each member of the verification group;

• Every member in the verification group will verify the block, sign, and send the signature to each member in the verification group;

• After verifying each group member, after collecting the signatures of a threshold number of others, the group signature is generated and broadcast to the entire network.

The flowchart is as follows:

## Introduction of Tokenomics

RPG (Rangers Protocol Gas) is the Rangers Protocol ecosystem token, with a total supply of 21 million pieces. In the economic system of Rangers Protocol, ecological nodes generate blocks that are divided into proposal and verification nodes. This system adopts an open participation mechanism, allowing all users to participate in the system’s operation.

RPG tokens will circulate among users, developers, investors, and ecological nodes.

• Investors(10%): Equal unlock (claim) each day. Token allocation for investors will be fully unlocked within 400 days.

• The Core team (14%): Core developers and maintainers, 8% of the remaining amount is released every 180 days.

• Incubators and consultants (7%): Incubators and strategic partners, 8% of the remaining amount is released every 180 days.

• Ecological community (49%): 8% of the remaining amount is released every 180 days, the ecological community consists of ecological nodes of both Rangers Mainnet and Rangers Connector.
Rangers Mainnet Ecological Nodes (35%): Proposal nodes (24.5%): join through RPG-staking election and provide special hardware. Verification nodes (10.5%): stake RPG, and provide required hardware.
Rangers Connector Ecological Nodes (14%)

• Ecological fund (20%): The unused amount is locked, community voting will be held, and relevant announcements made on the foundation website upon use.

• Treasury (0%): reward and penalty pool, dynamically balanced during operation, the value can be adjusted by community voting.

Minimum hardware requirements for mining exploration

• CPU： core8

• RAM: 16G

• HDD: 1T

• Network: 100M bandwidth

# Proposal Node

## The obligations of the proposal node

The obligations of the proposal node are as follows：
• Package transactions, generate candidate blocks, and submit to the corresponding verification group

• It requires staking of 2000 RPG to become qualified as a proposal node. With Rangers Protocol’s development and the governance mechanism’s improvement, RPG’s number staked as proposal nodes will continue to be adjusted.

• RPG cannot be unlocked during the period from the stake to block reward distribution. It can only be unlocked after the node reward is issued (10 hours). Each node can stake once in each block distribution cycle. When the rewarded proposal node distributes RPG, it will be done according to each node’s RPG stake ratio.

## Rewards of proposal node

The rewards of the proposal node are as follows:
• After the block is generated, the proposal group will receive 24.5% of the total block rewards.

• Each block-generating proposal node will get 7.35% of the total block rewards individually.

• All nodes in the proposal group, including the block-generating one, will share 17.15% of the remaining rewards according to the nodes’ stake ratio.

The calculation formula is as follow:
\begin{align}\begin{aligned}\begin{split}Q_{proposal node for block generation } &= Rangers Protocol current block reward\times\frac{3}{4}+\frac{stake amount of this node }{total stake amount of proposal nodes} \\ &\times RangerProtocol current block reward\times\frac{1}{2}\end{split}\\Q_{other proposal node}=\frac{stake amount of this node}{total stake amount of proposal nodes}\times Rangers Protocol current block reward\times\frac{1}{2}\end{aligned}\end{align}

# Proposal process

The proposal node will regularly calculate the VRF value based on the information of the block with the highest quantity and the staking information of all nodes. If VRF value meets the threshold, it comes into the proposal process:

• transaction packaging

• transaction implementation

• generate the status merkleTree root hash after executing the transaction

• select the verification group according to VRF

• calculate rewards of block generation

• generate the candidate blocks, including the following information: transaction hash table, transaction of merkleTree root hash, status merkleTree root hash, timestamp, height, the last Hash, proposal node id, the verification group id, VRF value, priority weighting, block hash,etc

• submit the candidate blocks to the verification group

# how to apply to become a proposal node

For the application of becoming a proposal node, please refer to: the specific process of the application of becoming a proposal node

# Verification Nodes

## Obligations of Verification Nodes

The obligations of a Verification node include the following:
• Participate in the creation process of Verification group regularly

• Validate the candidate block and provide the signature

• Collect sufficient signatures within the group and restore the group generation signatures

• It requires a minimum staking of 400 RPG to become qualified as a verification node and later a candidate verification node. Rangers Mainnet sets no restriction on the verification node application; a qualified verification node can enter the random pool by staking and then waiting to be selected into a verification group.

• A candidate verification node (for short, candidate node) can be selected into multiple verification groups simultaneously. The maximum number of verification groups that a candidate node can join is calculated by its staking value divided by 400, rounded down. The more a candidate node stakes, the more verification groups it can join simultaneously.

• The generation of Verification nodes still follows the VRF mechanism. RPG cannot be unlocked from stake to block generation allocation. It can only be unlocked within the specified time after node rewards allocation is completed. Each node can only stake once in each block allocation cycle.

## Verification Nodes Reward

The rewards for proposal nodes are as follows:
• After the block is generated, the verification group will receive 10.5% of the total block reward;

• All nodes in the verification group will be rewarded according to the proportion of each node’s token stake ratio

• A verification node can increase its staking at any time and for unlimited times without having to wait till the current distribution cycle concludes.

• During the period from staking to block reward distribution, RPG cannot be unlocked. It can only be unlocked after the node rewards are issued (10 hours).

The calculation formula is as follows:
$Q_{Verification signature node} = \frac{The node’s stake amount}{Total stake amount of proposal node}\times RangerProtocol current block reward\times\frac{2}{7}$

# Selection process

• Rangers Mainnet currently selects 5 to 10 members into a verification group. And the genesis group contains 20 members. The verification group members are randomly selected following the VRF consensus mechanism. Therefore, there exists the possibility for a candidate node not being selected into any verification group.

• If the current number of awaiting candidate nodes is below 10, as long as they’re in an active-responding status, they would all be selected into the upcoming verification group.

• If the current number of awaiting candidate nodes is above 10, the father group would randomly select 10 out of them.

• The possibility for each candidate node to be selected into a verification group is the same regardless of the value staked.

• The father group starts selecting the next verification group based on a certain block height without having to wait for the latest verification group to be dismissed. The selection for the next verification group will initiate as long as there are plenty of candidate nodes awaiting (a minimum of 5).

• Candidate nodes that weren’t selected into the latest verification group have the opportunity of joining the upcoming one.

# Verification process

• Verify the VRF value of the candidate block

• Calculate the verification group based on the VRF value and verify whether the verification group is selected

• Verify the priority weight of a candidate block. If a candidate block with a higher priority has been verified in this round of consensus, the block is not verified

• Execute the packaged transaction in the candidate block and verify the merkleTree root hash after the transaction

• Verify block generation rewards

• Verify block hash

# How to apply to become a verification node?

For details about how to apply to become a verification node, please refer to：Specific process for applying to become a verification node