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Proof of Elapsed Time (PoET)
What is Proof of Elapsed Time (PoET)?
Proof of Elapsed Time (PoET) is a consensus algorithm developed by Intel for permissioned blockchain networks. It's designed to be a more efficient and fair alternative to Proof of Work, using trusted execution environments to ensure randomness and fairness in the leader election process.
Key Characteristics
Randomized Leader Election: Uses a lottery system to select block creators.
Trusted Execution Environment: Relies on secure hardware (like Intel SGX) for fairness.
Energy Efficiency: Consumes less energy than Proof of Work.
Scalability: Designed to scale to large network sizes.
Permissioned Networks: Primarily used in private or consortium blockchains.
How Proof of Elapsed Time Works
Wait Time Assignment: Each node is assigned a random wait time.
Timer Execution: Nodes "sleep" for their assigned time in a trusted execution environment.
Wake-up and Block Creation: The first node to wake up creates the next block.
Block Propagation: The created block is propagated to the network.
Verification: Other nodes verify the validity of the elapsed time and the block.
Advantages of PoET
Energy Efficiency: Significantly reduces energy consumption compared to PoW.
Fairness: Provides a fair chance for all participants to create blocks.
Scalability: Can efficiently handle large numbers of participants.
Low Resource Requirements: Doesn't require expensive hardware or large stakes.
Predictable Block Time: Offers more consistent block creation times.
Challenges and Limitations
Hardware Dependency: Relies on specific hardware capabilities (e.g., Intel SGX).
Trust in Hardware Manufacturer: Requires trust in the hardware provider (e.g., Intel).
Limited to Permissioned Networks: Not suitable for public, permissionless blockchains.
Potential for Exploitation: Vulnerabilities in trusted execution environments could compromise the system.
Lack of Economic Incentives: Unlike PoW or PoS, doesn't inherently provide economic rewards.
Similar Terms
Burn: The act of permanently removing cryptocurrency from circulation.
Consensus Mechanism: The broader category of methods for achieving agreement on the state of a blockchain.
Proof of Stake (PoS): Consensus mechanism based on economic stake.