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Cc: Justus Ranvier <justusranvier@riseup.net>
Subject: [Bitcoin-development] [SPAM] Re: determining change addresses using
the least significant digits
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On Friday, February 06, 2015 3:16:13 AM Justus Ranvier wrote:
> On 02/04/2015 02:23 PM, Isidor Zeuner wrote:
> > Hi there,
> >
> > traditionally, the Bitcoin client strives to hide which output
> > addresses are change addresses going back to the payer. However,
> > especially with today's dynamically calculated miner fees, this may
> > often be ineffective:
> >
> > A user sending a payment using the Bitcoin client will usually
> > enter the payment amount only up to the number of digits which are
> > considered to be significant enough. So, the least significant
> > digits will often be zero for the payment. With dynamically
> > calculated miner fees, this will often not be the case for the
> > change amount, making it easy for an observer to classify the
> > output addresses.
> >
> > A possible approach to handle this issue would be to add a
> > randomized offset amount to the payment amount. This offset amount
> > can be small in comparison to the payment amount.
>
> Another possible approach is to randomize the number of change outputs
> from transaction to transaction.
>
> Doing this, it would be possible to make change outputs that mimic
> real spends (low number of s.d.)
This uses more data.
Why not just round change down (effectively rounding fee up)?
Luke
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