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by awelkie 2033 days ago
Can someone explain how block timing works in proof-of-stake systems? As I understand it, with proof-of-work the mining difficulty increases or decreases to maintain that each block is found in roughly the same amount of time. In proof-of-stake is there also a mechanism to regulate the time for each block to be added to the blockchain?
1 comments
dirtnugget 2033 days ago
No, as far as I understood the time between blocks in a PoS chain is basically just a timer (e.g. 10 seconds). There is no need to adjust that dynamically because there is no "race" to solve a problem. I guess it is even more predictable if it is not dynamically adjusted.
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zadler 2033 days ago
But that does have to be enforced via incentives/cryptography, and with reference to a clock.
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dirtnugget 2033 days ago
Well it is enforced by the protocol on which all node agree and there needs to be a mechanism for syncing clocks across nodes (also defined by the protocol) but they exist, e.g. https://ieeexplore.ieee.org/document/8946264

Not 100% sure what ETH is using here but there is a mechanism.

If someone would want to fake timestamps, they would need to deviate from the protocol and would thus not be on chain.

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Benmcdonald__ 2032 days ago
You are simply raising the fundamental difficulty with blockchains. How do you know what is the true chain in an adversary environment (the internet)? You gave us the question and no answer
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dirtnugget 2029 days ago
Validation of the longest chain, agreed upon by the protocol which the nodes are running. This is the absolute fundamental of this technology. This is not new and it has been working for more than a decade.
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dirtnugget 2029 days ago
* which the majority of nodes are running
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hanniabu 2033 days ago
This is incorrect. The difficulty is PoS adjusts to meet the target block time just like it does in PoW.
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dirtnugget 2033 days ago
I have to suspect that you are wrong. Can you provide a source? There is no mentioning of difficulty in the spec, instead there are predefined slot times:

https://github.com/ethereum/eth2.0-specs/blob/dev/specs/phas...

Here is how they sync: https://ieeexplore.ieee.org/document/8946264

Assuming they describe the BeaconBlocks mentioned here: https://github.com/ethereum/eth2.0-specs/blob/dev/specs/phas...

Also, which effect would an increased difficulty have?

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