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Cc: bitcoin-development@lists.sourceforge.net
Subject: Re: [Bitcoin-development] F2Pool has enabled full replace-by-fee
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On 6/20/2015 5:54 PM, Eric Lombrozo wrote:
> Perhaps it isn=92t prudent to push out changes to the relay policy that=
make these exploits even easier right now - but we NEED to be applying s=
ome kind of pressure on the merchant end to upgrade their stuff to be mor=
e resilient so that we have more room for changes on things like relay po=
licy without significant disruption to the network.
>
There's no need to worry about causing more problems by relaying
double-spends. After a year of watching, it's clear that already only
20% of hash power strictly obeys first-seen.
http://i.imgur.com/0bYXrjn.png
It may be surprising that
- The period of ambiguity is very short - just 2 seconds
(this makes sense, given the .5s median propagation time)
- Fast double-spends between 2 and 15 seconds are less successful
- The steady-state 80% respend success rate is reached after just 15
seconds
The >30s data point includes txes that were respent after a long time,
sometimes months. Those longer-term respends are to be expected, as
people reclaim stuck txes.
Paying attention to double-spends is an opportunity for wallets and
merchants . With 140 Bitcoin XT nodes online, you're probably already
receiving them. Most wallets, including vanilla core, don't even alert
when a double-spend of a wallet transaction appears in a block - even
though there may still be time to withhold delivery of the goods/services=
=2E
If FSS RBF gains miner share, fewer successful zero-conf double-spends
will occur. Only radical twisted logic finds that to be an undesirable
result.
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