🔢 Ordering Strategies: FIFO, Priority, Fairness

Understand different approaches to transaction sequencing

Watch how rollups batch transactions

📊 Transaction Ordering Strategies

How a sequencer orders transactions has profound implications for fairness, MEV, and user experience. Explore different ordering strategies and their trade-offs.

🎮 Strategy Comparison Tool

Select an ordering strategy to see its characteristics, trade-offs, and real-world adoption.

⏱️

First-In-First-Out (FIFO)

Complexity
Low
Fairness
High
Efficiency
Medium
Advantages
  • Simple to implement
  • Predictable ordering
  • No gas price competition
  • Fair time-based queue
Disadvantages
  • Vulnerable to spam
  • No MEV capture
  • Can be gamed with early submission
  • No priority mechanism
Real-World Example:Optimism (early version)

📈 Performance Metrics Calculator

Adjust gas price to see how it affects system metrics under the First-In-First-Out (FIFO) strategy.

1 gwei (cheap)50 gwei (expensive)
Avg Latency100ms
Throughput2000 TPS
Fairness Score85/100
MEV Risk30/100

🔄 Hybrid Approaches

Many L2s are experimenting with hybrid ordering strategies to balance fairness, efficiency, and user choice.

Arbitrum Timeboost

FIFO base with optional express lane auction for priority ordering. Users choose speed vs cost.

Chainlink FSS

Fair Sequencing Services using threshold encryption to prevent front-running while maintaining efficiency.

Priority Gas Auctions

Similar to EIP-1559, but with sequencer-specific priority fees that don't affect base execution.

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