carlton its time you re-read what RBF can do..
if the transaction is RBF people can change the transaction amounts.. its literaly even telling you with the first letter R=replace.
so if your going to do zero confirms acceptance. do not blindly trust a transactions that have either of these
has no fee
is RBF
whos taint shows that there have been other attempts of double spends before.
this is because
1. has no fee
https://bitcoincore.org/en/faq/optin_rbf/Sophisticated double spending attackers today use tools to map the network connectivity by making harmless looking conflicting spends and seeing which versions show up at which merchants and in which blocks. This allows them to craft two versions of the same transaction, one which they send to their victim and one which they send to miners for confirmation.
The presence of the non-replaceable payment to the merchant prevents his node from learning about a double-spend until it shows up in a block mined by a miner that was merely mining the thing they saw first. This simple, common pattern is sometimes further amplified by additional techniques such as using unconfirmed transaction chains, low fees, or non-standard transactions.
people can know which IP to send which transaction. EG send a
PayYourself tx directly to the pools with a fee. send a
PayRetailer without fee to a node known to be what the retailer uses to check. thus the retailer sees the
PayRetailer transaction first and the
PayYourself gets rejected by the retailers node.. but the important part is that the miners see
PayYourself first and rejects the
PayRetailer tx(especially because it has no fee anyway).. an guess which one gets confirmed!!
2. is RBF
https://bitcoincore.org/en/faq/optin_rbf/Opt-in RBF is a change to memory pool and network relay code that allows those wallets to optionally add a signal to their transactions which tells full nodes that those particular transactions may be updated (replaced) up until the point that they get confirmed in a new block.
even though RBF does include a fee(so point 1 wont raise a red flag). RBF can do something different..by messing with the amounts of the output and increase the fee it can cheange the transaction.. its literally in the name Replace By Fee. so if someone is paying you a TX you have to logically ask.. if they have no reason to mess/replace the transaction why would they opt for RBF. the answer is because there is a risk the transaction can change.(hint: red flag)
3. that there is a chance the customer may try a double-spend if there are signs of double spends linked to the originators address from past transactions. EG they practiced it, before doing it for real. or this is not the first time they scammed a retailer.(hint: red flag)
no one is saying everyone will try it. but atleast knowing what to look out for allows you to spot some red flags to be a bit mindful about whether you hand over the goods instantly or to keep the customer in conversation or delay the goods if the red flags appear..
that way if everyone just paid a fee and there was no sign of double spend taint. no reason to RBF. the goods can be released.
if however there was no fee.. or there was an RBF. or there was some taint.. you can delay handing over the goods for X seconds to see if any other similar transactions got relayed around the network incase the one you seen first was presented to you before you got to see the one presented to the mining pool first.. then you can see which one got accepted by the mining pools first to know if your going to get paid the right amount or not.
..
i seriously wonder about carlton. even trying to suggest bitcoin is perfect and people should remain blind and accept zero-confirms without even doing any basic risk analysis..
i love bitcoins (carlton loves monero). but atleast its best to be honest and tell people there are risks/issues. that way they can protect themselves and prepare themselves.
bitcoin is great but it is not perfect. atleast knowing the issues helps people to work around them.
..
this is how i think carlton thinks
blindly accept zero confirms because there is only 3% chance of being scammed so its an acceptable loss
this is how i think
add some analysis tools that look for red flags. instantly hand goods to the 97% that dont throw up flags and delay the goods handover of the 3% that are throwing up flags until certain its not a double spend
