Subject: Re: [bitcoin-dev] Design for a CoinSwap implementation for massively improving Bitcoin privacy and fungibility

From: "Mr. Lee Chiffre" <[email-masked]>
Date: Tue, 9 Jun 2020 17:43:40 -0700

>
> === Combining multi-transaction with routing ===
>
> Routing and multi-transaction must be combined to get both benefits. If
> Alice owns multiple UTXOs (of value 6 BTC, 8 BTC and 1 BTC) then this is
> easy with this configuration:
>
>              Alice
>     (6 BTC) (8 BTC) (1 BTC)
>        |       |       |
>        |       |       |
>        v       v       v
>               Bob
>     (5 BTC) (5 BTC) (5 BTC)
>        |       |       |
>        |       |       |
>        v       v       v
>             Charlie
>     (9 BTC) (5 BTC) (1 BTC)
>        |       |       |
>        |       |       |
>        v       v       v
>             Dennis
>     (7 BTC) (4 BTC) (4 BTC)
>        |       |       |
>        |       |       |
>        v       v       v
>              Alice
>

Great work Chris and you have my respects for your contributions to
Bitcoin. A concern I have with bitcoin is scalability and privacy. Both
are important. The reasons people bash on Monero is also the same issue
Bitcoin has. The very large transaction size to achieve acceptable privacy
on a distributed financial network. Im not shilling Monero here. I am only
saying that bitcoin transactions with similar privacy properties are at
least equally as large as Monero transactions. Coinjoin on Monero can be
compared to ring signatures in Monero from the view of using decoys to
help conceal the source. From this proposal is this to say that
transactions will be at least 12 times larger in size to achieve the
property of privacy that bitcoin is currently missing?

Another thing to consider is that if coinswaps cannot be sent as a payment
then a coinswap needs to take place after every transaction to keep the
privacy and unlinkability from your other bitcoin transactions.

I always thought that CoinSwap would be and is a very much needed thing
that needs developed. The ability to swap coins with other people in a
trustless way and way that is not linkable to the public blockchain. But
how can this be scalable at all with the multiple branches and layers?
This is a good idea in theory but my concern would be the scalability
issues this creates.

Do you have any comments on this?
Thank you

-- 
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PGP 97F0C3AE985A191DA0556BCAA82529E2025BDE35