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Proof-of-activity (PoA)

Proof-of-activity (PoA)

Proof of activity is a hybrid between proof of stake and proof of work. Blocks are generated through PoW mining mechanisms and then a switch to a proof of stake style mechanism occurs where validator nodes stake tokens in order to be chosen to sign these mined blocks.

Proof of activity is a consensus mechanism used in decentralized blockchain networks to validate transactions. It is a hybrid approach that combines aspects of proof of work and proof of stake consensus mechanisms.

Proof of work and proof of stake are both designed to prevent 51% attacks - a malicious action in which one individual or party controls a majority of the mining power in the cryptocurrency network and can then include invalid transactions in the blockchain. Proof of activity combines these mechanisms into a single two step-process:

  1. Proof of work for miners to compete to find the block and earn the block reward. The greater percentage of the network's total computing power a miner has, the greater the probability that they will find a block.
  2. Proof of stake to validate/sign the new block. The greater the percentage of the total cryptocurrency supply a staker has, the greater the probability that they will be chosen to validate the block.

Proof of activity adds a second line of defense against 51% attacks because an attacker would theoretically need to have both 51% or more of the network's total mining power and 51% or more of the coins staked in the network in order to successfully pull off the attack.

Decred is a cryptocurrency that uses the proof of activity consensus mechanism. Espers is another.

Timeline

Charlie Lee makes Proof of Activity Proposal on bitcointalk

Charlie Lee, creator of Litecoin, originally proposed Proof of Actvity in a thread on the bitcointalk forum.

People

Name
Role
Related Golden topics

Charlie Lee

Creator

Litecoin

Further reading

Title
Author
Link
Type

A CryptoCoderz Team Project White Paper Written by the CryptoCoderz Team February 20 th 2018 (Version 1.0 Release)

CryptoCoderz Team

PDF

Overview - Decred Documentation

Web

Proof of Activity Proposal

Charlie Lee

Web

Proof of Activity: Extending Bitcoin’s Proof of Work via Proof of Stake

Iddo Bentov, Charles Lee, Alex Mizrahi, Meni Rosenfeld

Academic paper

Documentaries, videos and podcasts

Title
Date
Link

Decred Proof of Stake

April 20,2017

Companies

Company
CEO
Location
Products/Services

References