Consensus Implementation

Y Protocol implements a Simplified Proof-of-Stake (SPoS) consensus mechanism with Byzantine fault tolerance and validator slashing.

2/3+ Majority

BFT

Slashing

Core Implementation

SimplePOSConsensus Structure

Core consensus engine implementation

pub struct SimplePOSConsensus {
    pub validator_votes: HashMap<String, ValidatorVote>,
    pub block_proposals: HashMap<u64, Block>,
    pub consensus_threshold: f64,  // 0.67 (2/3 majority)
    pub current_height: u64,
    pub active_validators: Vec<ValidatorInfo>,
    pub vote_history: HashMap<u64, HashMap<String, ValidatorVote>>,
    pub slashing_manager: Option<Arc<Mutex<SlashingManager>>>,
}

Source: /crates/consensus/src/consensus/pos.rs

Voting Mechanism

Consensus Threshold:

67% (2/3+ majority)

Voting Window:

2 seconds

Block Finality:

Single Slot

Validators vote on proposed blocks. Blocks are finalized when 2/3+ majority is reached.

Network Timing

Block Time Target:

4 seconds

Proposal Phase:

1.33 seconds

Voting Phase:

1.33 seconds

Finalization Phase:

1.33 seconds

Network phases: Proposal → Voting → Finalization → Broadcast

Validator Management

Requirements

Minimum Stake:

10,000 YPC

Selection Weight Cap:

1M YPC

Uptime Requirement:

95%+

Slashing Conditions

Double Signing:

5% slash

Invalid Block:

2% slash

Extended Downtime:

1% slash

Selection Algorithm

Stake-weighted random selection

Validators are selected based on their stake proportion, with a maximum weight cap for decentralization.

Consensus Process

Block Consensus Flow

Step-by-step consensus mechanism

Validator Selection

Stake-weighted random selection chooses block proposer

Block Proposal

Selected validator proposes new block with transactions

Voting Phase

Validators vote on the proposed block (3-second window)

Block Finalization

Block finalized when 2/3+ majority votes received

Reward Distribution

Block rewards and fees distributed to participants

Security Features

Byzantine Fault Tolerance

Tolerates up to 33% malicious validators
Double-spend protection
Long-range attack mitigation
Nothing-at-stake prevention

Implementation Details

No chain reorganizations
Finality achieved once 2/3+ validators reach consensus
Slashing for misbehavior
Vote history tracking