What Is Proof of Elapsed Time (PoET)? (Cryptocurrency)

Proof of elapsed time (PoET) is a blockchain network consensus mechanism algorithm that prevents high resource utilization and high energy consumption and keeps the process more efficient by following a fair lottery system. The algorithm uses a randomly generated elapsed time to decide mining rights and block winners on a blockchain network. By running a trusted code within a secure environment, the PoET algorithm also enhances transparency by ensuring lottery results are verifiable by external participants.

Key Takeaways

  • Proof of elapsed time (PoET) is a consensus algorithm developed by Intel Corporation that enables permissioned blockchain networks to determine block winners and mining rights.
  • PoET follows a lottery system that spreads the chances of winning equally across network participants, giving every single node the same chance of winning.
  • The PoET algorithm generates a random wait time for each node in the blockchain network; each node must go to sleep for that duration.
  • The node with the shortest wait time will wake up first and will win the block, thus being allowed to commit a new block to the blockchain.
  • The PoET workflow is similar to Bitcoin's proof of work (PoW) but consumes less power because it allows a miner’s processor to sleep and switch to other tasks for the specified time, thereby increasing efficiency.

Understanding Proof of Elapsed Time (PoET)

Proof of elapsed time (PoET) is a consensus mechanism algorithm that is often used on the permissioned blockchain networks to decide the mining rights or the block winners on the network. Permissioned blockchain networks are those which require any prospective participant to identify themselves before they are allowed to join. Based on the principle of a fair lottery system where every single node is equally likely to be a winner, the PoET mechanism is based on spreading the chances of winning fairly across the largest possible number of network participants.

The working of the PoET algorithm is as follows. Each participating node in the network is required to wait for a randomly chosen time period, and the first one to complete the designated waiting time wins the new block. Each node in the blockchain network generates a random wait time and goes to sleep for that specified duration. The one to wake up first—that is, the one with the shortest wait time—wakes up and commits a new block to the blockchain, broadcasting the necessary information to the whole peer network. The same process then repeats for the discovery of the next block.

The PoET network consensus mechanism needs to ensure two important factors. First, the mechanism ensures that the participating nodes genuinely select a time that is indeed random and not a shorter duration chosen purposely by the participants in order to win. Second, the mechanism establishes that the winner has indeed completed the waiting time.

PoET and Intel Corporation

The PoET concept was invented during early 2016 by Intel Corporation (INTC), the famous chip manufacturing giant. It offers a readymade high tech tool to solve the computing problem of "random leader election." The ingrained mechanism allows applications to execute trusted code in a protected environment, and this ensures that both requirements—for randomly selecting the waiting time for all participating nodes and genuine completion of waiting time by the winning participant—are fulfilled.

In conjunction with other organizations such as the Linux Project and IBM, Intel sponsored Hyperledger Sawtooth that supports the PoET consensus mechanism. Hyperledger Sawtooth is an umbrella blockchain development group that uses an open-source enterprise blockchain-as-a-service platform. When creating PoET, the developers saw its potential to be used on permissioned blockchain networks to decide the mining rights or the block winners on the network.

Benefits of Proof of Elapsed Time (PoET)

Essentially, the workflow is similar to the consensus mechanism followed by Bitcoin's proof of work (PoW) algorithm, but without its high power consumption. Instead of being resource-intensive, it allows a miner’s processor to sleep and switch to other tasks for the specified time, thereby increasing its efficiency.

The mechanism of running trusted code within a secure environment also takes care of many other necessities of the network. It ensures that the trusted code indeed runs within the secure environment and is not alterable by any external participant. It also ensures that the results are verifiable by external participants and entities, thereby enhancing the transparency of the network consensus.

PoET controls the cost of the consensus process and keeps it nimble so that the cost remains proportional to the value derived from the process, a key requirement for the cryptocurrency economy to continue flourishing.