What is the performance difference between Proof of Authority (PoA) and Proof of Work (PoW)? In terms of transactions per second.

1 Answer 1


Performance: The transaction throughput is limited (among other things) by the block size. By how many transactions one can fit in a block.

Proof of Authority is a centralized consortium chain and can handle potentially hundreds of thousands (or millions) of transactions per second because the scalability is not bounded by consensus on what is the correct or longest chain, but by the hardware used.

This means we can scale vertically, use large data centers to process and store all of this data. We simply allow them to place a large amount of transactions into a single block.

The block producers are few and known. Users of the blockchain trust that they will behave honestly and not collude to perform an attack.

Proof of Work on the other hand does not rely on trusting a small number of block producers to achieve consensus. Instead it allows anyone to participate in block production and achieve consensus on watching what is the longest chain. The transaction throughput on PoW is not (so much) bounded by the protocol, but by a choice users are forced to make between decentralization and transaction throughput. To illustrate this, I will use Bitcoin as an example:

Choice 1 | Small blocks - This means we can only fit a few transactions into a single block which results in low transaction throughput (~7 tx/s). But also means that mining does not require a lot storage. The system is more decentralized.

Choice 2 | Scale Bitcoin through PoA-sized blocks - In this case, users decide that each block may now be as big as 1024Gb instead of Satoshi's 1Mb. Now we can fit many more transactions in a single block and increase bitcoin's throughput. However to run a node you now need high end machines, a lot of storage and a high speed internet connection to process blockchain! Suddenly cannot afford to verify that block producers are following the rules agreed, instead you have to trust them: a regression to the status quo.

  • 2
    "hundreds of thousands (or millions)" sounds a little bit too optimistic. Do you know if anyone did benchmarks on this?
    – ivicaa
    Commented Feb 22, 2018 at 20:26
  • 2
    I don't know of any benchmarks, but this is what Delegated Proof-of-Stake (EOS, Bitshares, NEO) claim to deliver, which are really Proof-of-Authority chains with diferent protocols for authority selection.
    – mtsfaria
    Commented May 14, 2018 at 14:54
  • 2
    "not bounded by consensus on what is the correct or longest chain, but by the hardware used" If one of the sealer node have weaker hardware than the other sealer nodes, will the TPS drop?
    – Nyxynyx
    Commented Jul 15, 2018 at 18:06
  • No, they will simply not be able to keep up with the chain and never sync.
    – mtsfaria
    Commented Jun 2, 2022 at 21:51

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.