In this poetically named consensus mechanism, network participants prove that they have slept for a random amount of time before being able to mint a block.
POET was released by Intel in 2016 and was originally aimed at trusted computing using Intel CPU's. A special instruction set called Software Guard Extensions (SGX) allows programs to run under a trusted environment (cryptographically signed).
When a node joins a POET network, it downloads some executable content from a public blockchain. This content is then run, generating this node's private keys.
The content received from the blockchain is used to generate a random number, often called a timer object. This random timer object tells the node how long it must wait before waking up again.
Once the POET node wakes up it mints a block and sends it into the network. The block which reaches most participants is accepted, all others discarded.
This looks a lot like Bitcoin's Proof of Work (PoW) system - and it is!
While Bitcoin's PoW system forces a wait using brute force (a difficult to solve cryptographic puzzle), POET forces a wait through trusted computing.
Programmers would call Bitcoin's system a busy wait system, whereas POET is a lazy algorithm. Bitcoin's proof of work spends massive amounts of energy during the wait period and POET does not.
Return to main article: ELI5 Summary of cryptocurrency consensus mechanisms