Subject: Re: [bitcoin-dev] OP_RETURN inside TapScript

From: Peter Todd <[email-masked]>
Date: Wed, 16 Mar 2022 14:21:30 -0400

On Thu, Feb 24, 2022 at 10:02:08AM +0100, vjudeu via bitcoin-dev wrote:
> Since Taproot was activated, we no longer need separate OP_RETURN outputs to be pushed on-chain. If we want to attach any data to a transaction, we can create "OP_RETURN <anything>" as a branch in the TapScript. In this way, we can store that data off-chain and we can always prove that they are connected with some taproot address, that was pushed on-chain. Also, we can store more than 80 bytes for "free", because no such taproot branch will be ever pushed on-chain and used as an input. That means we can use "OP_RETURN <1.5 GB of data>", create some address having that taproot branch, and later prove to anyone that such "1.5 GB of data" is connected with our taproot address.

There are two use-cases for OP_RETURN: committing to data, and publishing data.
Your proposal can only do the former, not the latter, and there are use-cases
for both.

-- 
https://petertodd.org 'peter'[:-1]@petertodd.org