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Add spec changes for ZIPs 207 and 214. 

Signed-off-by: Daira Hopwood <daira@jacaranda.org>
This commit is contained in:
Daira Hopwood 2020-07-13 18:41:50 +01:00
parent bc809dae5d
commit b2f033f84d
3 changed files with 178 additions and 32 deletions
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190
protocol/protocol.tex
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@ -1475,6 +1475,17 @@ electronic commerce and payment, financial privacy, proof of work, zero knowledg
\newcommand{\BlockSubsidy}{\mathsf{BlockSubsidy}}
\newcommand{\MinerSubsidy}{\mathsf{MinerSubsidy}}
\newcommand{\FoundersReward}{\mathsf{FoundersReward}}
\newcommand{\FundingStreams}{\mathsf{FundingStreams}}
\newcommand{\fs}{\mathsf{fs}}
\newcommand{\fsNumerator}{\fs\mathsf{.Numerator}}
\newcommand{\fsDenominator}{\fs\mathsf{.Denominator}}
\newcommand{\fsStartHeight}{\fs\mathsf{.StartHeight}}
\newcommand{\fsEndHeight}{\fs\mathsf{.EndHeight}}
\newcommand{\fsValue}{\fs\mathsf{.Value}}
\newcommand{\fsAddressList}{\fs\mathsf{.AddressList}}
\newcommand{\fsAddressIndex}{\fs\mathsf{.AddressIndex}}
\newcommand{\fsNumAddresses}{\fs\mathsf{.NumAddresses}}
\newcommand{\fsRedeemScriptHash}{\fs\mathsf{.RedeemScriptHash}}
\newcommand{\SlowStartInterval}{\mathsf{SlowStartInterval}}
\newcommand{\SlowStartShift}{\mathsf{SlowStartShift}}
\newcommand{\SlowStartRate}{\mathsf{SlowStartRate}}
@ -1484,14 +1495,18 @@ electronic commerce and payment, financial privacy, proof of work, zero knowledg
\newcommand{\NumFounderAddresses}{\mathsf{NumFounderAddresses}}
\newcommand{\FounderAddressChangeInterval}{\mathsf{FounderAddressChangeInterval}}
\newcommand{\FoundersFraction}{\mathsf{FoundersFraction}}
\newcommand{\FundingStreamAddressChangeInterval}{\mathsf{FundingStreamAddressChangeInterval}}
\newcommand{\FundingStreamAddressPeriod}{\mathsf{FundingStreamAddressPeriod}}
\newcommand{\BlockHeight}{\mathsf{height}}
\newcommand{\FounderAddressAdjustedHeight}{\mathsf{FounderAddressAdjustedHeight}}
\newcommand{\FoundersRewardLastBlockHeight}{\mathsf{FoundersRewardLastBlockHeight}}
\newcommand{\Halving}{\mathsf{Halving}}
\newcommand{\HalvingNum}{\mathsf{halving}}
\newcommand{\HeightForHalving}{\mathsf{HeightForHalving}}
\newcommand{\FounderAddress}{\mathsf{FounderAddress}}
\newcommand{\FounderAddressList}{\mathsf{FounderAddressList}}
\newcommand{\FounderAddressIndex}{\mathsf{FounderAddressIndex}}
\newcommand{\RedeemScriptHash}{\mathsf{RedeemScriptHash}}
\newcommand{\FounderRedeemScriptHash}{\mathsf{FounderRedeemScriptHash}}
\newcommand{\blockSubsidy}{\term{block subsidy}}
\newcommand{\minerSubsidy}{\term{miner subsidy}}
@ -3116,24 +3131,34 @@ considered disjoint, even if they have the same bit pattern.}
}
\lsubsection{Block Subsidy and Founders' Reward}{subsidyconcepts}
\lsubsection{Block Subsidy\canopy{, Funding Streams,} and Founders' Reward}{subsidyconcepts}
Like \Bitcoin, \Zcash creates currency when \blocks are mined. The value created on
mining a \block is called the \defining{\blockSubsidy}. It is composed of a \defining{\minerSubsidy} and a
\defining{\foundersReward}. As in \Bitcoin, the miner of a \block also receives \defining{\transactionFees}.
mining a \block is called the \defining{\blockSubsidy}.
The calculations of the \blockSubsidy, \minerSubsidy, and \foundersReward depend on
the \blockHeight, as defined in \crossref{blockchain}.
\precanopy{The \blockSubsidy is composed of a \defining{\minerSubsidy} and a \defining{\foundersReward}.}
These calculations are described in \crossref{subsidies}.
\canopyonward{The \blockSubsidy is composed of a \minerSubsidy and a series of \defining{\fundingStreams}.}
As in \Bitcoin, the miner of a \block also receives \defining{\transactionFees}.
The calculations of the \blockSubsidy, \minerSubsidy, \notcanopy{and }\foundersReward\canopy{, and \fundingStreams}
depend on the \blockHeight, as defined in \crossref{blockchain}.
The calculations are described in \crossref{subsidies}.
\lsubsection{Coinbase Transactions}{coinbasetransactions}
The first (and only the first) \transaction in a block is a \defining{\coinbaseTransaction},
which collects and spends any \minerSubsidy and \transactionFees paid by \transactions
included in this \block. The \coinbaseTransaction{} \MUST also pay the \foundersReward
as described in \crossref{foundersreward}.
included in this \block.
\precanopy{The \coinbaseTransaction{} \MUST also pay the \foundersReward as described in \\
\crossref{foundersreward}.}
\canopyonward{The \coinbaseTransaction \MUST also pay the \fundingStreams as described in \\
\crossref{fundingstreams}.}
\lsubsection{Mainnet and Testnet}{networks}
@ -5735,8 +5760,8 @@ contain the \transaction in which a \note was output.
\vspace{-2ex}
\nnote{
Normally only \noteCiphertexts of \transactions in \blocks need to be decrypted.
A client \MAY attempt to decrypt a \noteCiphertext of a \transaction in the \mempool,
using the next \blockHeight for $\BlockHeight$. However, in that case it \MUSTNOT assume that
A client \MAY attempt to decrypt a \noteCiphertext of a \transaction in the \mempool\canopy{,
using the next \blockHeight for $\BlockHeight$}. However, in that case it \MUSTNOT assume that
the \transaction will be mined and \MUST treat the decrypted information as provisional.
} %nnote
} %sapling
@ -9761,9 +9786,9 @@ in its \blockHeader is defined as $\floor{\hfrac{2^{256}}{\ToTarget(\nBits) + 1}
\introlist
\lsubsection{Calculation of Block Subsidy and Founders' Reward}{subsidies}
\lsubsection{Calculation of Block Subsidy\canopy{, Funding Streams,} and Founders' Reward}{subsidies}
\crossref{subsidyconcepts} defines the \defining{\blockSubsidy, \minerSubsidy, and \foundersReward}.
\crossref{subsidyconcepts} defines the \blockSubsidy, \minerSubsidy,\notcanopy{ and} \foundersReward\canopy{, and \fundingStreams}.
Their amounts in \zatoshi are calculated from the \blockHeight using
the formulae below.
@ -9771,6 +9796,8 @@ Let\notbeforeblossom{ the constants} $\SlowStartInterval$,\, $\PreBlossomHalving
\blossom{$\PostBlossomHalvingInterval$,\, $\BlossomActivationHeight$,\, }$\MaxBlockSubsidy$,
and $\FoundersFraction$ be as defined in \crossref{constants}.
\canopy{Let $\FundingStreams$ be as specified in \crossref{zip214fundingstreams}.}
\vspace{1ex}
\begin{formulae}
\item $\SlowStartShift \typecolon \Nat := \hfrac{\SlowStartInterval}{2}$
@ -9784,7 +9811,7 @@ and $\FoundersFraction$ be as defined in \crossref{constants}.
\vspace{0.5ex}
\item $\BlockSubsidy(\BlockHeight \typecolon \Nat) := \begin{cases}
\SlowStartRate \mult \BlockHeight,&\caseif \BlockHeight < \hfrac{\SlowStartInterval}{2} \\[1.4ex]
\SlowStartRate \mult (\BlockHeight + 1),&\caseif \hfrac{\SlowStartInterval}{2} \leq \BlockHeight \\[0.4ex]
\SlowStartRate \mult (\BlockHeight + 1),&\caseif \hfrac{\SlowStartInterval}{2} \leq \BlockHeight \\
&\text{ and } \BlockHeight < \SlowStartInterval \\[1.4ex]
\floor{\hfrac{\MaxBlockSubsidy}{2^{\Halving(\BlockHeight)}}}\!\!,&\notblossom{\caseotherwise}\notbeforeblossom{\caseif \SlowStartInterval \leq \BlockHeight} \\[-1ex]
\notbeforeblossom {
@ -9798,7 +9825,21 @@ and $\FoundersFraction$ be as defined in \crossref{constants}.
0,&\caseotherwise
\end{cases}$
\item $\MinerSubsidy(\BlockHeight \typecolon \Nat) := \BlockSubsidy(\BlockHeight) - \FoundersReward(\BlockHeight)$.
\canopy {
\vspace{0.5ex}
\item for $\fs \in \FundingStreams$,\, $\fsValue(\BlockHeight) :=$
\vspace{-0.5ex}
\item \tab $\begin{cases}
0,&\caseif \BlockHeight < \CanopyActivationHeight \\
\floor{\BlockSubsidy(\BlockHeight) \mult
\hfrac{\fsNumerator}{\fsDenominator}},&\caseif \fsStartHeight \leq \BlockHeight
\text{ and } \BlockHeight < \fsEndHeight \\
0,&\caseotherwise
\end{cases}$
} %canopy
\item $\MinerSubsidy(\BlockHeight) := \BlockSubsidy(\BlockHeight) - \FoundersReward(\BlockHeight)
\canopy{\,- \ssum{\fs\, \in\, \FundingStreams}{} \fsValue(\BlockHeight)}$.
\end{formulae}
\introsection
@ -9907,22 +9948,22 @@ Define:
\blossom{\maximum\Of{\setof{\BlockHeight \typecolon \Nat \suchthat \Halving(\BlockHeight) < 1}}}$\,.
\end{formulae}
Let $\RedeemScriptHash(\BlockHeight \typecolon \Nat)$ be the standard redeem script hash, as defined in
Let $\FounderRedeemScriptHash(\BlockHeight \typecolon \Nat)$ be the standard redeem script hash, as specified in
\cite{Bitcoin-Multisig}, for the P2SH multisig address with Base58Check form
given by $\FounderAddressList_{\,\FounderAddressIndex(\BlockHeight)}$.
\vspace{-1ex}
\consensusrule{
A \coinbaseTransaction for \blockHeight $\BlockHeight \in \range{1}{\FoundersRewardLastBlockHeight}$
\consensusrule{\precanopy{
A \coinbaseTransaction at $\BlockHeight \in \range{1}{\FoundersRewardLastBlockHeight}$
\MUST include at least one output that pays exactly $\FoundersReward(\BlockHeight)$ \zatoshi
with a standard P2SH script of the form \ScriptOP{HASH160} \;$\RedeemScriptHash(\BlockHeight)$\; \ScriptOP{EQUAL}
with a standard P2SH script of the form \ScriptOP{HASH160} \;$\FounderRedeemScriptHash(\BlockHeight)$\; \ScriptOP{EQUAL}
as its $\scriptPubKey$.
}
}}
\vspace{1ex}
\begin{pnotes}
\item No \foundersReward is required to be paid for $\BlockHeight > \FoundersRewardLastBlockHeight$
(i.e.\ after the first halving), or for $\BlockHeight = 0$ (i.e.\ the \genesisBlock).
(i.e.\ after the first halving), or for $\BlockHeight = 0$ (i.e.\ the \genesisBlock)\canopy{, or after \Canopy activation}.
\item The \foundersReward addresses are not treated specially in any other way, and
there can be other outputs to them, in \coinbaseTransactions or otherwise.
In particular, it is valid for a \coinbaseTransaction with
@ -9942,6 +9983,108 @@ as its $\scriptPubKey$.
\end{nnotes}
} %blossom
\canopy{
\lsubsection{Payment of Funding Streams}{fundingstreams}
The \defining{\fundingStreams} are paid by outputs in the \coinbaseTransaction, to one of a pre-defined
set of addresses, depending on the \blockHeight.
A \fundingStream $\fs$ is defined by a \blockSubsidy fraction (represented as a numerator and
denominator), a start \blockHeight (inclusive), an end \blockHeight (exclusive), and a sequence
of address representations:
\begin{formulae}
\item $\fsNumerator \typecolon \PosInt$
\item $\fsDenominator \typecolon \PosInt$
\item $\fsStartHeight \typecolon \Nat$
\item $\fsEndHeight \typecolon \Nat$
\vspace{-1ex}
\item $\fsAddressList \typecolon \typeexp{\byteseqs}{\PosInt}$.
\end{formulae}
Define:
\begin{formulae}
\item $\HeightForHalving(\HalvingNum \typecolon \Nat) :=
\minimum\Of{\setof{\BlockHeight \typecolon \Nat \suchthat \Halving(\BlockHeight) = \HalvingNum}}$
\item $\FundingStreamAddressChangeInterval := \PostBlossomHalvingInterval / 48$
\item $\FundingStreamAddressPeriod(\BlockHeight) :=
\floor{\hfrac{\BlockHeight - (\HeightForHalving(1) - \PostBlossomHalvingInterval)}{\FundingStreamAddressChangeInterval}}$.
\end{formulae}
For each \fundingStream $\fs$, define:
\begin{formulae}
\item $\fsAddressIndex(\BlockHeight) := 1 + \FundingStreamAddressPeriod(\BlockHeight) - \FundingStreamAddressPeriod(\fsStartHeight)$
\item $\fsNumAddresses := \fsAddressIndex(\fsEndHeight - 1)$.
\end{formulae}
$\fsAddressList$ \MUST be of length $\fsNumAddresses$. Each element of $\fsAddressList$
\MUST represent either a \transparent P2SH address as specified in \crossref{transparentaddrencoding},
or a \Sapling \paymentAddress as specified in \crossref{saplingpaymentaddrencoding}.
Recall from \crossref{subsidies} the definition of $\fsValue$. A \fundingStream $\fs$ is
``active'' at \blockHeight $\BlockHeight$ when $\fsValue(\BlockHeight) > 0$.
\consensusrule{
\canopyonward{
The \coinbaseTransaction at \blockHeight $\BlockHeight$ \MUST contain at least
one output per \fundingStream $\fs$ active at $\BlockHeight$, that pays
$\fsValue(\BlockHeight)$ \zatoshi in the prescribed way to the stream's
recipient address represented by $\fsAddressList_{\fsAddressIndex(\BlockHeight)}$.
\begin{itemize}
\item The ``prescribed way'' to pay a \transparent P2SH address is to use a standard
P2SH script of the form \ScriptOP{HASH160} \;$\fsRedeemScriptHash(\BlockHeight)$\; \ScriptOP{EQUAL}
as the $\scriptPubKey$. Here $\fsRedeemScriptHash(\BlockHeight)$ is the standard
redeem script hash for the recipient address given by
$\fsAddressList_{\,\fsAddressIndex(\BlockHeight)}$ in Base58Check form. The
standard redeem script hash is specified in \cite{Bitcoin-Multisig} for
P2SH multisig addresses, or \cite{Bitcoin-P2SH} for other P2SH addresses.
\item The ``prescribed way" to pay a \Sapling address is as defined in \cite{ZIP-213};
that is, following the post-\Heartwood consensus rules specified
for \Sapling outputs of \coinbaseTransactions in \crossref{txnencoding}.
\end{itemize}
} %canopyonward
} %consensusrule
\begin{pnotes}
\item The \fundingStream addresses are not treated specially in any other way, and
there can be other outputs to them, in \coinbaseTransactions or otherwise.
In particular, it is valid for a \coinbaseTransaction to have
other outputs, possibly to the same address, that do not meet the criterion
in the above consensus rule, as long as at least one output meets it.
\end{pnotes}
\lsubsubsection{ZIP 214 Funding Streams}{zip214fundingstreams}
Let $\CanopyActivationHeight$ be as defined in \crossref{constants}.
\vspace{0.5ex}
\cite{ZIP-214} defines three \fundingStreams:
\renewcommand{\arraystretch}{1}
\begin{formulae}
\item \begin{tabular}{|l|c|c|c|c|}
\hline
Stream & Numerator & Denominator & Start height & End height \\\hline
\texttt{FS\_ZIP214\_ECC} & $7$ & $100$ & $\CanopyActivationHeight$ & $2726400$ \\
\texttt{FS\_ZIP214\_ZF} & $5$ & $100$ & $\CanopyActivationHeight$ & $2726400$ \\
\texttt{FS\_ZIP214\_MG} & $8$ & $100$ & $\CanopyActivationHeight$ & $2726400$ \\\hline
\end{tabular}
\end{formulae}
\begin{pnotes}
\item $\CanopyActivationHeight$ is different between \Mainnet and \Testnet.
\item On \Testnet, the \activationHeight of \Canopy will be before the first halving.
Therefore, the consequence of the above rules for \Testnet is that the amount sent to
each recipient \fundingStream address will initially (before \Testnet \blockHeight $1046400$)
be double the corresponding initial amount on \Mainnet. This reduces to the same amount
as on \Mainnet, from \Testnet \blockHeights $1046400$ (inclusive) to $2726400$ (exclusive).
\end{pnotes}
} %canopy
\lsubsection{Changes to the Script System}{scripts}
@ -10631,6 +10774,9 @@ Peter Newell's illustration of the Jubjub bird, from \cite{Carroll1902}.
``the test network'' to \Testnet. This follows the terminology used
in ZIPs.
\item Update stale references to \Bitcoin documentation.
\canopy{
\item Add changes for \cite{ZIP-207} and \cite{ZIP-214}.
}
\end{itemize}
@ -10910,7 +11056,7 @@ Peter Newell's illustration of the Jubjub bird, from \cite{Carroll1902}.
of the \blockChain. This inconsistency was pointed out by NCC Group
in their \Blossom specification audit.
\blossom{
\item Revert changes for funding streams from Withdrawn ZIP 207.
\item Revert changes for \fundingStreams from Withdrawn ZIP 207.
} %blossom
\end{itemize}

6
zip-0214.html
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@ -59,21 +59,21 @@ Discussions-To: &lt;https://forum.zcashcommunity.com/t/community-sentiment-polli
</thead>
<tbody>
<tr>
<td><code>FS_ECC</code></td>
<td><code>FS_ZIP214_ECC</code></td>
<td>7</td>
<td>100</td>
<td>1046400</td>
<td>2726400</td>
</tr>
<tr>
<td><code>FS_ZF</code></td>
<td><code>FS_ZIP214_ZF</code></td>
<td>5</td>
<td>100</td>
<td>1046400</td>
<td>2726400</td>
</tr>
<tr>
<td><code>FS_MG</code></td>
<td><code>FS_ZIP214_MG</code></td>
<td>8</td>
<td>100</td>
<td>1046400</td>

14
zip-0214.rst
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@ -102,13 +102,13 @@ ZIP 207 [#zip-0207]_ SHALL be activated in Canopy.
The following funding streams are defined for Mainnet:
========== =========== ============= ============== ============
Stream Numerator Denominator Start height End height
========== =========== ============= ============== ============
``FS_ECC`` 7 100 1046400 2726400
``FS_ZF`` 5 100 1046400 2726400
``FS_MG`` 8 100 1046400 2726400
========== =========== ============= ============== ============
================= =========== ============= ============== ============
Stream Numerator Denominator Start height End height
================= =========== ============= ============== ============
``FS_ZIP214_ECC`` 7 100 1046400 2726400
``FS_ZIP214_ZF`` 5 100 1046400 2726400
``FS_ZIP214_MG`` 8 100 1046400 2726400
================= =========== ============= ============== ============
As specified in [#zip-0207]_, a funding stream is active for a span of blocks
that includes the block at its start height, but excludes the block at its end