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Out of interest, what would you say is a reasonable minimum amount of disk space for a user to have to devote to their bitcoin node, such that the number of nod

Out of interest, what would you say is a reasonable minimum amount of disk space for a user to have to devote to their bitcoin node, such that the number of nodes does not cause significant extra centralisation (over and above the centralisation of mining pools and development teams)?

tromp 6y ago
Only an archive node needs to keep a copy of the entire chain. But every full node needs to download and verify all of it, so it's more a question of bandwidth and time. It would be nice to be able to so within a day.
- dane-pgp 6y ago
  That's interesting, thank you. As a quick calculation, the bitcoin blockchain recently[0] reached 300 GB which, spread over a day, would require a download speed of 27.8 MBit/s. For comparison, "the global average download speed on fixed broadband is 85.73 Mbps as of September 2020"[1] so even if block sizes were triple their historic values it would still be possible for average global users to wait less than a day to complete the initial download. [0] https://decrypt.co/42427/bitcoin-blockchain-grows-to-300-gigabytes-in-size https://decrypt.co/42427/bitcoin-blockchain-grows-to-300-gig... [1] https://worldpopulationreview.com/country-rankings/internet-speeds-by-country https://worldpopulationreview.com/country-rankings/internet-...
  - CryptoPunk 6y ago
    Initial sync up of a full node doesn't need all 300 GB of chain history to be downloaded/validated. A pruned state can be downloaded with no more trust assumptions than that required to trust the software distribution channel where you download the Bitcoin software from to actually serve Bitcoin. Anyway, every one in the world doesn't need to run a full node. Even a few thousand geographically distributed full nodes is enough to offer resistance to network shut down, and there are more than a few million people that are capable of running a full node of a hypothetical Bitcoin with 1 GB sized blocks, which only requires downloading 1.67 MB/s of transactions to keep up with validation. That's a 1000 expansion of Bitcoin's throughput, letting Bitcoin become the world's most widely used currency. The entire small block narrative is built on a shaky foundation that ignores the massive benefits of enabling more people to transact directly on the Bitcoin blockchain.
    - tromp 6y ago
      > A pruned state can be downloaded with no more trust assumptions than that required to trust the software distribution channel where you download the Bitcoin software from to actually serve Bitcoin. Nonsense. Bitcoin software releases come with widely publicized checksums and signatures from reputable sources.
      - dane-pgp 6y ago
        Couldn't those reputable sources also provide widely publicized checksums and signatures for a pruned blockchain state?
        tromp 6y ago
        The pruned blockchain state changes every block. More importantly, Bitcoin is ideologically opposed to the idea of checkpoints, as they run counter to the Longest Chain Rule that says the true state is whatever valid chain has the most cumulative work. Even if that chain is the result of a very deep reorg that invalidates the last checkpoint.
      - CryptoPunk 6y ago
        I am only including those "widely publicized checksums and signatures from reputable sources" in my definition of "software distribution channel".

tromp 6y ago

Only an archive node needs to keep a copy of the entire chain. But every full node needs to download and verify all of it, so it's more a question of bandwidth and time. It would be nice to be able to so within a day.

dane-pgp 6y ago
That's interesting, thank you. As a quick calculation, the bitcoin blockchain recently[0] reached 300 GB which, spread over a day, would require a download speed of 27.8 MBit/s. For comparison, "the global average download speed on fixed broadband is 85.73 Mbps as of September 2020"[1] so even if block sizes were triple their historic values it would still be possible for average global users to wait less than a day to complete the initial download. [0] https://decrypt.co/42427/bitcoin-blockchain-grows-to-300-gigabytes-in-size https://decrypt.co/42427/bitcoin-blockchain-grows-to-300-gig... [1] https://worldpopulationreview.com/country-rankings/internet-speeds-by-country https://worldpopulationreview.com/country-rankings/internet-...
- CryptoPunk 6y ago
  Initial sync up of a full node doesn't need all 300 GB of chain history to be downloaded/validated. A pruned state can be downloaded with no more trust assumptions than that required to trust the software distribution channel where you download the Bitcoin software from to actually serve Bitcoin. Anyway, every one in the world doesn't need to run a full node. Even a few thousand geographically distributed full nodes is enough to offer resistance to network shut down, and there are more than a few million people that are capable of running a full node of a hypothetical Bitcoin with 1 GB sized blocks, which only requires downloading 1.67 MB/s of transactions to keep up with validation. That's a 1000 expansion of Bitcoin's throughput, letting Bitcoin become the world's most widely used currency. The entire small block narrative is built on a shaky foundation that ignores the massive benefits of enabling more people to transact directly on the Bitcoin blockchain.
  - tromp 6y ago
    > A pruned state can be downloaded with no more trust assumptions than that required to trust the software distribution channel where you download the Bitcoin software from to actually serve Bitcoin. Nonsense. Bitcoin software releases come with widely publicized checksums and signatures from reputable sources.
    - dane-pgp 6y ago
      Couldn't those reputable sources also provide widely publicized checksums and signatures for a pruned blockchain state?
      - tromp 6y ago
        The pruned blockchain state changes every block. More importantly, Bitcoin is ideologically opposed to the idea of checkpoints, as they run counter to the Longest Chain Rule that says the true state is whatever valid chain has the most cumulative work. Even if that chain is the result of a very deep reorg that invalidates the last checkpoint.
    - CryptoPunk 6y ago
      I am only including those "widely publicized checksums and signatures from reputable sources" in my definition of "software distribution channel".