hush-v3-whitepaper/hush-v3.tex

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\begin{document}

\title{\doctitle \\
\Large \docversion}
\author{
\Large \leadauthor\hairspace\thanks{\;duke@leto.net}
}
\date{\today}
\maketitle

\renewcommand{\abstractname}{}
\vspace{-8ex}
\begin{abstract}
\normalsize \noindent \textbf{Abstract.}

\Hush originally was a source code fork of the \Zcash 1.0.8 codebase. Hush was
    originally called "Zdash" and is not a chain fork, Hush mined it's own
    unique genesis block.

    ...

\vspace{2.5ex}
\noindent \textbf{Keywords:}~ \StrSubstitute[0]{\keywords}{,}{, }.
\end{abstract}

\vspace{-10ex}
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\newpage

\nsection{Introduction}

\nsection{Things Staying The Same}

\begin{itemize}
\item 21M total supply
\item Block reward
\item Block time
\item Halving interval
\item Delayed-Proof-Of-Work
\end{itemize}

\nsection{Things Changing}

\begin{itemize}
    \item New Genesis Block
    \item Sprout Disabled
    \item First Pure Sapling Chain, with Super Fast Shielded Transactions
    \item s/ZEC/KMD/ as upstream
    \item New main Github repo
    \item Addition of 10\% Founders Reward
    \item Address prefix change (t1,t3 becomes R,b)
    \item RPC and P2P ports
    \item Enable CryptoConditions (Custom Consensus)
    \item Block Size increase to 4MB
    \item Shielding Rule
    \item TLS Support
\end{itemize}


\nsection{Hush v1-v2 Total Supply Bug}

The original Hush devs added the original pre-mine in such a way that Hush would
have a supply greater than the intended 21,000,000 after about 30 years. This
fact was discovered in the process of emulating the current Hush supply curve
(halving interval) on our new Komodo-based chain. This bug will be corrected on
our new chain (Hush v3) by ceasing block rewards when total supply hits 21M
coins, as intended.

As a reminder, NONE of the current Hush team received any the original 0.76\%
(160,000 HUSH) pre-mine. All of the original Hush developers who received the
reward have long since left the project.

The current Hush chain (version 2) will attain a supply of 21,000,000 coins at
Block 5922239 which will have a Block Reward of 0.09765625 HUSH. This happens
between the 7th and 8th halvings.

But because the original devs of Hush added a pre-mine of 160,000 HUSH in blocks
1 through 4, the current Hush supply curve will continue past the 21M supply
mark until Block 26039999 when supply is 21159937.4895 HUSH and the last block
reward of 1 satoshi is awarded just before the 31st halving.

The core issue is that blocks 1 through 4 had a block reward of 40,000 each
instead of 12.5 each in the GetBlockSubsidy() function defined in main.cpp, but
the overall emission schedule was not modified to take this into account.

This mistake would eventually lead to an extra 159,937.4895 HUSH of total supply
beyond the intended totaly supply of 21M, which would happen after about 30
years, between the 7th and 8th halvings.

This bug in the supply curve of Hush will be fixed during the migration to a
Komodo asset chain, where we can use ac\_end=N to specify a block when block
rewards should cease. This will allow us to enforce the intended 21M total
supply of Hush.

To calculate the value of ac\_end for the new Hush chain:

ac\_end = 5922239 - (number of blocks in old Hush chain) - (zero block reward transition period)
ac\_end = 5922239 - 500000 - 128
ac\_end = 5422111

To clarify, Hush will have a consensus rule that block rewards stop at block
5422111 which will enforce a total supply of 21M coins.

\nsection{New Blockchain Size}

The Hush blockchain will essentially be compressed, down from its current size
of about 3.4GB to a few megabytes. This is related to the fact that there are
about 30,000 unique addresses on the Hush blockchain which contain funds.

This compression will greatly improve the user experience of new Hush users,
which can install and sync a full node in just a few minutes.

\nsection{Special Thanks}

Special thanks to jl777 and the greater Komodo community for inspiring a new
generation of cypherpunks to innovate outside the constraints of Bitcoin and
Zcash core communities.

Special thanks to radix42, Savior Of The Memo Field, for mentoring me in my
early days as a cryptocoin dev.

Remember, remember, the 5th Of November.

\nsection{References}

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\end{document}