@ -141,12 +141,28 @@ need botnet or supercomputer-level resources to attack the same length chains as
de-anonymizing attackers will focus on studying short linkability chains with a lot of additional metadata from
timing analysis, amount analysis and potentially passive or active dust attacks.
## Non-determinism
### Non-determinism
Combinatorial explosion can only protect us so much. It is only one layer of defense and surely will not save us
from the inevitable quantum computers which are being optimized every day.
When adding zutxos, to break the ITM/Metaverse metadata attacks at a deep level, we must break a deep assumption
that is baked deep into Bitcoin wallet behavior: determinism.
Combinatorial explosion can only protect us so much. It is only one layer of defense.
Given the exact same wallet.dat, Bitcoin, Zcash and Hush will act in *exactly the same way* when sending a transaction, every
single time. Given all input data, one can predict the behavior of what will happen. Obviously, this is a very good idea in Bitcoin,
for total supply and issuance accountability. But this also contributes to Bitcoin being a "surveillance coin", that perfectly
preserves metadata until the end of time.
When adding zutxos, to break the ITM/Metaverse metadata attacks at a deep level, we must break a deep assumption
that is baked deep into Bitcoin: determinism.
Zcash had no reason to change this and they did not, and so this behavior is baked in deep to all Bitcoin and Zcash forks.
In light of the ITM/Metaverse attack, this determinism is considered dangerous by the author. The reason is that the
ITM/Metaverse attack utilizes the fact that wallet operations are predictable to extract more metadata than previously thought possible from z2z and t=>z xtns. The only way to prevent that is to break the assumption of predictable wallet behavior.
# Conclusions
Sietch-enabled Hush Protocol can be thought of as using the ideas of combinatorial explosion and non-determinism to thwart brand-new
blockchain analysis techniques. Non-determinism is the stronger weapon, but it does not add enough privacy unless we add in the appropriate amount of combinatorial explosion to linkability analysis. Together they are a potent weapon which also give us a knob
to turn to increase future security, i.e. the minimum number of zaddr outputs allowed in a transaction.
This is why both techniques complement each other and have a greater privacy improvement when used together.
