public inbox for bitcoindev@googlegroups.com
 help / color / mirror / Atom feed
From: Thomas Guyot-Sionnest <dermoth@aei•ca>
To: Adam Tamir Shem-Tov <tshachaf@gmail•com>,
	Bitcoin Protocol Discussion
	<bitcoin-dev@lists•linuxfoundation.org>
Subject: Re: [bitcoin-dev] Solving the Scalability Problem on Bitcoin
Date: Sat, 26 Aug 2017 17:31:11 -0400	[thread overview]
Message-ID: <a9015271-7f61-7bba-c550-afdd76319b21@aei.ca> (raw)
In-Reply-To: <CACQPdjphPmSC7bmicXGytuD3YAXYmsEGOECTTTuLfB_5iqDQGw@mail.gmail.com>

[-- Attachment #1: Type: text/plain, Size: 3054 bytes --]

Pruning is already implemented in the nodes... Once enabled only unspent
inputs and most recent blocks are kept. IIRC there was also a proposal
to include UTXO in some blocks for SPV clients to use, but that would be
additional to the blockchain data.

Implementing your solution is impossible because there is no way to
determine authenticity of the blockchain mid way. The proof that a block
hash leads to the genesis block is also a proof of all the work that's
been spent on it (the years of hashing). At the very least we'd have to
keep all blocks until a hard-coded checkpoint in the code, which also
means that as nodes upgrades and prune more blocks older nodes will have
difficulty syncing the blockchain.

Finally it's not just the addresses and balance you need to save, but
also each unspent output block number, tx position and script that are
required for validation on input. That's a lot of data that you're
suggesting to save every 1000 blocks (and why 1000?), and as said
earlier it doesn't even guarantee you can drop older blocks. I'm not
even going into the details of making it work (hard fork, large block
sync/verification issues, possible attack vectors opened by this...)

What is wrong with the current implementation of node pruning that you
are trying to solve?

--
Thomas

On 26/08/17 03:21 PM, Adam Tamir Shem-Tov via bitcoin-dev wrote:
>
> <B> Solving the Scalability issue for bitcoin </B> <BR>
>
> I have this idea to solve the scalability problem I wish to make public.
>
> If I am wrong I hope to be corrected, and if I am right we will all
> gain by it. <BR>
>
> Currently each block is being hashed, and in its contents are the hash
> of the block preceding it, this goes back to the genesis block.
>
> <BR>
>
> What if we decide, for example, we decide to combine and prune the
> blockchain in its entirety every 999 blocks to one block (Genesis
> block not included in count).
>
> <BR>
>
> How would this work?: Once block 1000 has been created, the network
> would be waiting for a special "pruned block", and until this block
> was created and verified, block 1001 would not be accepted by any nodes.
>
> This pruned block would prune everything from block 2 to block 1000,
> leaving only the genesis block. Blocks 2 through 1000, would be
> calculated, to create a summed up transaction of all transactions
> which occurred in these 999 blocks.
>
> <BR>
>
> And its hash pointer would be the Genesis block.
>
> This block would now be verified by the full nodes, which if accepted
> would then be willing to accept a new block (block 1001, not including
> the pruned block in the count).
>
> <BR>
>
> The new block 1001, would use as its hash pointer the pruned block as
> its reference. And the count would begin again to the next 1000. The
> next pruned block would be created, its hash pointer will be
> referenced to the Genesis Block. And so on..
>
> <BR>
>
> In this way the ledger will always be a maximum of 1000 blocks.
>
>


[-- Attachment #2: Type: text/html, Size: 4851 bytes --]

  reply	other threads:[~2017-08-26 21:31 UTC|newest]

Thread overview: 8+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2017-08-26 19:21 Adam Tamir Shem-Tov
2017-08-26 21:31 ` Thomas Guyot-Sionnest [this message]
2017-08-26 22:32   ` Adam Tamir Shem-Tov
2017-08-27  5:18     ` Thomas Guyot-Sionnest
     [not found]     ` <CAN6UTayLR6rqSuHrsyF+7fFM4Fht7vbgXYRWzBRYXw8i43WzBw@mail.gmail.com>
2017-08-27 12:10       ` Leandro Coutinho
2017-08-27  3:52   ` Btc Ideas
2017-08-27  0:27 ` Weiwu
2017-08-27 13:19 Matthew Beton

Reply instructions:

You may reply publicly to this message via plain-text email
using any one of the following methods:

* Save the following mbox file, import it into your mail client,
  and reply-to-all from there: mbox

  Avoid top-posting and favor interleaved quoting:
  https://en.wikipedia.org/wiki/Posting_style#Interleaved_style

* Reply using the --to, --cc, and --in-reply-to
  switches of git-send-email(1):

  git send-email \
    --in-reply-to=a9015271-7f61-7bba-c550-afdd76319b21@aei.ca \
    --to=dermoth@aei$(echo .)ca \
    --cc=bitcoin-dev@lists$(echo .)linuxfoundation.org \
    --cc=tshachaf@gmail$(echo .)com \
    /path/to/YOUR_REPLY

  https://kernel.org/pub/software/scm/git/docs/git-send-email.html
Be sure your reply has a Subject: header at the top and a blank line before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox