Subject: Re: [bitcoin-dev] [Lightning-dev] Removing the Dust Limit

From: shymaa arafat <[email-masked]>
Date: Wed, 18 Aug 2021 21:06:30 +0200

Dear Sir,

I'm not discussing the dust limit here, but I'm suggesting some mitigations
to the dust problem which tackles almost the same points mentioned here
especially the scalability of the UTXOS set and the corresponding Merkle
proofs/witnesses in Utreexo or any similar design ....
.
I suggest:
1-Dust UTXOS, along with burned & non-standard UTXOS, to be stored
separately in secondary storage; their Hashes in a separate Merkle too in
any accumulator design
(an earlier draft of the idea
https://bitcointalk.org/index.php?topic=5343748.new#new)
.
-In fact, the idea of separating the real UTXO values was first suggested in
https://royalsocietypublishing.org/doi/10.1098/rsos.180817
In their words
"Similarly, one can think of a two-tier data structure where a UTXO subset
containing UTXOs with a low probability of being selected such as dust is
kept on disk, while the other UTXOs are kept in memory."
.
2-I suggest also that existing dust UTXOS (from the same paper, in some
cases a UTXO could be added as an extra input with the cost of 68*fee/byte)
, to be selected with large UTXO whenever they fit in a spending ( use one
large & one small to get rid of the small)
.
3-In general when user is not willing to leave the dust to the fee, and if
there's no dust UTXOS, do not let the coin selection algorithm select the
closest match; let it choose the smallest that doesn't create dust.
For example if there's UTXOS 0.00013 & 0.00012 and user want to spend
0.0001198 choose 0.00013 so that the change is not dust (with same cost).
.
Thank you for your time,
This is the first time I send a suggestion to your emailing list, so sorry
if I missed any regulations
.
Shymaa M. Arafat