Trade Fee Payment using unidirectional payment channels

[ChrisSon15]

https://github.com/bisq-network/bisq-musig/blob/main/concept/tradefeepayment.md

I wrote this in the repositorym so I have version control and history. Please read, Its not complete and considered 'alpha' quality at this point. Please comment here.

[suddenwhipvapor]

So even DPTs will be paid in full to one selected BM instead of sharing them across all BMs... which is obvious, because of the payment channels.
As BM doesn't need to be online at the time of opening the channel or paying the fee, is it okay to be online at least once each month (or however long is the expiry period)?
Is there a mechanism where the channel is automatically closed when almost all funds are spent?
Will the channel close anyway after a maximum defined period (irrelevant from the process of expiration), to "refresh" the BM distribution?
I guess that by using silent payments, BMs won't be able to use just any wallet/address they wish? Is it possible to just configure a static address instead?

[tsjk]

The major convenience of silent payments is that the payer can singlehandedly derive onchain-addresses for the payee given only the silent payment address, in a way that conceals, from a third party, that multiple generated addresses may go to the same recipient. This is quite good as it decreases on-line requirements for the recipient, while keeping the address generation private.
I haven't used Joinmarket much and am not well-versed in pros and cons. But, afaik one can import private keys. So, to have the amounts in your Joinmarket wallet (at mix level 0, of course) you need not do an extra tx. This of course only works if the output can be key-spent. No idea yet where we are with how this all is really going to work.

[suddenwhipvapor]

thank you for the input, I guess I should be educating myself on the possibility of importing private keys to that extent, not a major issue per se since JM has a hot wallet in the first place.

[suddenwhipvapor]

https://github.com/JoinMarket-Org/joinmarket-clientserver/blob/master/docs/USAGE.md#importprivkeys
for reference

[suddenwhipvapor]

so from what I get in jm docs and looking around, jm allows setting the mix depth to import the key into, but will only accept compressed private keys and only derive bc1q... addresses from it

[ChrisSon15]

The common issue with BM payouts is that they will need to be consolidated at some point in the future (admittedly less so with payment channels, but still), so eventually the real addresses behind a silent payment will become known anyway, or at least that's my evaluation but I'm open to being corrected

The point of using silent payment is that others cannot learn that the payment came from a bisq payment transaction. Using static addresses signals to the world, that this is a payment to a concrete bisq contributor.
Consolidating several / many small utxos is partially mitigated through the use of a channel, but consolidation is not giving up privacy. Just have a look at the mempool, there are any consolidation transactions, so you are in good company with a transaction like that.

[ChrisSon15]

I have updated the article, please have a fresh look
https://github.com/bisq-network/bisq-musig/blob/main/concept/tradefeepayment.md
main changes

• the script spend to let the trader take all money after a timedelay and penalise an unresponsive BM has been removed.
• silent payment has been more detailed
• proof of payment introduces a short-cut.

please review.