Safest client to run while this whole bip110 situation resolves?

[takuma sato]

I was wondering what would the best client to run until the bip110 resolves. I was originally more on the bip110 side as I think Ordinals are a problem that make running nodes a hard task on some of the most secure laptops (which happen to be older ones that can be run with an open source BIOS) but as it stands im no longer sure I support that side as I sure do not want another hard fork situation in which you are unsure which side will end up becoming the main chain.

So while this resolves, what client is best if you need to send some coins to an exchange? I know it also depends on what the exchange is running. What I want is that if there is a hardfork, I get the coins on both ends of the fork so I can decide what to do (typically I have just held both sides and then dumped when the outcome was clearer)

As of right now I have installed bitcoin-29.3.knots20260210. I assume whether this one of the latest pre-30 Core version would be good reasonable candidates to wait for some months until we see a resolution.

[Satofan44]

I was wondering what would the best client to run until the bip110 resolves. I was originally more on the bip110 side as I think Ordinals are a problem that make running nodes a hard task on some of the most secure laptops (which happen to be older ones that can be run with an open source BIOS) but as it stands im no longer sure I support that side as I sure do not want another hard fork situation in which you are unsure which side will end up becoming the main chain.

So while this resolves, what client is best if you need to send some coins to an exchange? I know it also depends on what the exchange is running. What I want is that if there is a hardfork, I get the coins on both ends of the fork so I can decide what to do (typically I have just held both sides and then dumped when the outcome was clearer)

As of right now I have installed bitcoin-29.3.knots20260210. I assume whether this one of the latest pre-30 Core version would be good reasonable candidates to wait for some months until we see a resolution.

There is no replay protection that is created by the Bitcoin Knots side, therefore there is no client that can be used in order to provide you with any kind of protocol protection. Therefore, if you have 1 BTC before the split and you make a valid transaction which sends that 1 BTC to the exchange and it is a valid transaction under Bitcoin Core and Bitcoin Knots, then this same transaction can be included on both chains (replayed). If you think about these kinds of forks without replay protection, you don't really suddenly have 2 BTC (1 on each chain) but you have a transaction which has consumed some UTXO (and which can be broadcast across all forks without replay protection).

Only a split that includes replay protection or differences in the transaction-format allows a separation of coins. If you want to retain coins on both chains, then you should not send send any BTC to an exchange during this time. You need to wait out a resolution of the situation. It is possible that the Knots fork never happens or really materializes or that there is no easy mechanism for a safe UTXO split at all. For this particular purpose, whether you are running Bitcoin Knots, an old Bitcoin Core or a new Bitcoin Core version makes no difference at all.

[nc50lc]

So while this resolves, what client is best if you need to send some coins to an exchange?

Do you mean before the split?
Because every transaction that you make before the chain split will be mirrored to the other blockchain, so there's nothing to replay in that case.
In other words: You already spent your coins so you don't get forked coins.

Or

You mean a precaution against replay protection after the split?
If so, you'll need to have both clients and enable "coin-control" to be able to create a transaction in the "Altcoin blockchain" that spends the forked UTXO back to your own wallet's address.
That way, even if someone replayed it in the Bitcoin blockchain, you're still the receiver.
(if it's replayed, don't proceed to the next step)

Then after it's confirmed, proceed to spend the Bitcoin UTXO to your intended exchange.
Its forked UTXO in the Altcoin chain is already spent so the transaction can't be replayed there.

Coin-control is a hard requirement for this to spend the correct UTXO, unless you have a single UTXO in your wallet.

[ABCbits]

You mean a precaution against replay protection after the split?
If so, you'll need to have both clients and enable "coin-control" to be able to create a transaction in the "Altcoin blockchain" that spends the forked UTXO back to your own wallet's address.
That way, even if someone replayed it in the Bitcoin blockchain, you're still the receiver.
(if it's replayed, don't proceed to the next step)

Until now, there's no mention of word "replay" on Bitcoin knots on GitHub[1-2]. So IMO just assume replay attack would happen and start by creating such TX that also violate BIP 110 (just send dust to uncompressed P2PK or create OP_RETURN with size more than 83 bytes). But it's not straightforward either, since BIP 110 only enforced after block height 963648 + 1 on BIP 110 chain[3] and i could miss small detail that make such process more risky than expected.

[1] https://github.com/bitcoinknots/bitcoin/issues?q=replay
[2] https://github.com/bitcoinknots/bitcoin/pulls?q=replay
[3] https://github.com/bitcoin/bips/blob/master/bip-0110.mediawiki#user-content-Deployment

[nc50lc]

-snip- and start by creating such TX that also violate BIP 110

That's actually a good prevention specific to Knots' case since it couldn't be broadcasted in their chain.

My example above is more of a precaution and universal to forked chains without replay protection.

[DaveF]

....
As of right now I have installed bitcoin-29.3.knots20260210. I assume whether this one of the latest pre-30 Core version would be good reasonable candidates to wait for some months until we see a resolution.

It's resolved. knots is dead, knots is 75+ blocks behind.
Also seems to be worthless since no exchange or other service has even mentioned it's existence. So you can worry about the lack of replay protection but even if you loose those coins it's not like they were worth anything.

Keep in mind, knots is just a fork of core & core only supports the current version and 2 previous versions. So with 32.x being released in a couple of months that means that 29.x will no longer have any support / fixes / updates except what luke puts in. Now, people have been running unsupported versions of bitcoin for years and years with no issue, but it's something to consider.

-Dave

[athanred]

there is no client that can be used in order to provide you with any kind of protocol protection

I successfully splitted my coins through P2PK, if you use any of my splitted coin in your transaction, then your coins will also split correctly: https://bitcointalk.org/index.php?topic=5590674.msg67025339#msg67025339

non-BIP-110: https://mempool.space/tx/4b9b6cdfbd9dd6e14f593f014b6bfe4a823089d90a01ed212b82999c65e63919
BIP-110: https://mempool.guide/tx/f0693758e229ba82d3ece2e419714f60617b77c5148c8fda7c382cbf8931cf48