Developing a Self-hosted Grin payment processor Wordpress Plugin

[Anynomous]

@grn

Secure would be if the shop owner would put them manually into cold storage (for example with Ledger wallet), but that would require manual interaction, which is a hurdle and I think the requirement to have a second wallet is a hurdle as well.

In that case the shop owner receives the transaction and still would require to sign the transaction manually using his ledger, e.g. do this once in the weekend, that should be manageable.

@grn

which is a hurdle and I think the requirement to have a second wallet is a hurdle as well.

I think in pracitice this will not be an hurdle since most people do have exchange wallets any-how, and they do accept the manageable risks that come with it.

@grn

With traditional crypto, the shop just needs to watch a wallet (public or with view key). It doesn’t even need special software, as it could just call an API for that. Incoming TX means, invoice was paid, so release the goods. With Grin the shop needs to implement interactive transactions with hot keys on the server and on top of that needs to be quicker than an attacker to put received coins into cold storage.

With Grin it is not that different, e.g. both traditional crypto and Grin need to be connected to see if a transaction worked out. So the main difference is the hot-keys which is indeed a trade-off.
Traditional crypto is easier to use than Grin, but only marginally so. Grin on the other hand offers also quite some benefits, such as 1) improved privacy, 2) low transaction costs for a privacy coin, 3) being able to run a raspberry Pi or phone as a full node since you require so little storage for the full chain, which is a great security benefit.
There are many ways to deal with the risk of hotkeys that reduce risks for shop owners.
E.g. 1) In a physical store, air-gaping, the payments are done through QR code, there is not internet talk between the wallets and as such lower security risk. 2) using a hard-ware wallet to sign emptying of temporary usage accounts, secure but would require an action from the shop-owner.
Using an another wallet (online, off-line or with hardware-wallet) to deposit regularly also means that someone will have a hard time and very low reward for hacking you.

In summary, I do not think interactive versus non-interactive transactions are that important of a difference. In the end it is how the ecosystem is shaped and how easy it is to use that determines if people will actually use it. Therefore, I think that is where we should put our effort. Work towards grin hardware wallet, work towards payment processors that are as easy to use as any other crypto.

@grn

What is the business argument that convinces an e-commerce owner to still use Grin under these circumstances?

Many shops still accept and send Bitcoin through insecure channels, leaking the IP of where the wallet is stored and transaction value. These are bigger risks in my opinion than those that come with Grin.
At least with Grin, only the buyer and shop owner know the amount and IP’s are hidden.
For shops that now accept Bitcoin lightning-payments with cheaper transaction cost and better privacy, they have the exact same difficulties as Grin, requiring interactivity. Still many shop manage to accept lightning payments, meaning it is somewhat manageable.