IntersectMBO · JaredCorduan · Oct 28, 2020 · Oct 23, 2020 · Oct 26, 2020
@@ -54,25 +54,30 @@ \section{Blockchain layer}
 In Figure~\ref{fig:functions:to-ma}, we give the functions that will be used
 to transition from a Shelley chain state into a chain state that provides multi-asset support.
 The only part of the state that is affected by the transition is the UTxO. For ease of
-reading, we use different notation here to define the UTxO update, and specify
-explicitly only the change to the UTxO, implying that every other part of the
-state is unaffected.
+reading, we keep the function $\fun{updateChainStateUTxO}$ abstract, which simply transforms the
+UTxO that is nested deeply inside the chain state with the provided function.
 
 %%
 %% Figure - Shelley to MA Transition
 %%
 \begin{figure}[htb]
+ %
+ \emph{Abstract function}
+ %
+ \begin{align*}
+ & \fun{updateChainStateUTxO} \in (\ShelleyUTxO \to \UTxO) \to \ShelleyChainState \to \ChainState \\
+ & \text{update the UTxO in a Shelley chain state}
+ \end{align*}
+ %
+ \emph{Chain state update}
+ %
  \begin{align*}
  & \fun{mkUTxO} ~\in~ \ShelleyUTxO \to \UTxO \\
  & \fun{mkUTxO}~\var{utxo} ~=~ \{~ \var{txin} \mapsto (a,\fun{coinToValue}~c) ~\vert~
- \var{txin} \mapsto \var{(a,c)}\in ~\var{utxo}~\} \\
- & \text{make UTxO with MA}
+ \var{txin} \mapsto \var{(a,c)}\in ~\var{utxo}~\}
  \nextdef
  & \fun{toMA} \in ~ \ShelleyChainState \to \ChainState \\
- & \fun{toMA}~cs = cs' \\
- & \where \\
- & ~~~~ cs'_{utxo} = \fun{mkUTxO}~\var{utxo} \\
- & \text{transform Shelley chain state to a MA-supporting state}
+ & \fun{toMA}~cs = \fun{updateChainStateUTxO}~\fun{mkUTxO}
  \end{align*}
  \caption{Shelley to Multi-Asset Chain State Transtition}
  \label{fig:functions:to-ma}

@@ -57,7 +57,7 @@ \section{Rewards and the Epoch Boundary}
  & \where \\
  & ~~~~ (~\var{rewards},~\var{delegations},~\var{ptrs},~\wcard,~\wcard,~\wcard)
  = \var{dstate} \\
- & ~~~~ (~\var{poolParams}~\wcard,~\wcard) = \var{pstate} \\
+ & ~~~~ (~\var{poolParams},~\wcard,~\wcard) = \var{pstate} \\
  & ~~~~ \var{stakeRelation} = \left(
  \left(\fun{stakeCred_b}^{-1}\cup\left(\fun{addrPtr}\circ\var{ptr}\right)^{-1}\right)
  \circ\left(\hldiff{\fun{utxoAda}}~{\var{utxo}}\right)

@@ -6,10 +6,9 @@ \section{Script Constructors and Evaluation}
  \begin{align*}
  \fun{validateScript} & \in\Script\to
  \powerset{\KeyHash}\to\TxBody\to\Bool \\
- \fun{validateScript} & ~s~\var{vhks}~\var{txb}
- ~\var{txb}~\var{utxo} =
+ \fun{validateScript} & ~s~\var{vhks}~\var{txb}~=
  \begin{cases}
- \fun{evalMultiSigScript}~s~vhks & \text{if}~s \in\ScriptMSig \\
+ \fun{evalMultiSigScript}~s~vhks & \text{if}~s \in\ScriptNI \\
  \fun{evalFPS}~s~\var{vhks} ~txb & \text{if}~s \in\ScriptMPS \\
  \mathsf{False} & \text{otherwise}
  \end{cases}
@@ -21,7 +20,7 @@ \section{Script Constructors and Evaluation}
 We have updated the
 $\fun{validateScripts}$ function, to allow for the validation of both the
 multi-signature scripts and forging policy scripts, calling the appropriate
-evaluator for each type of script, see~\ref{fig:functions-validate}.
+evaluator for each type of script, see Figure~\ref{fig:functions-validate}.
 
 \begin{note}
  This appendix will change if we change anything about the language, it will go

@@ -0,0 +1,31 @@
+\section{Protocol Parameters}
+
+In Shelley, the size of a UTxO entry was bounded from above, which
+will not be the case anymore. The protocol parameter
+$\var{minUTxOValue}$ was used to prevent an attack on the UTxO size,
+but as there is no upper bound on the memory usage of a UTxO entry
+anymore, this parameter will be retired in favor of two new
+parameters, $\var{adaPerUTxOByte}$ and $\var{outputSizeConstants}$.
+
+
+\begin{figure*}[htb]
+ \emph{Protocol Parameters}
+ %
+ \begin{equation*}
+ \begin{array}{r@{~\in~}lr}
+ \var{adaPerUTxOByte} \mapsto \nonnegReals & \PParams & \text{conversion factor for UTxO storage space}\\
+ \var{outputSizeConstants} \mapsto \Z \times \Z \times \Z & \PParams & \text{constants for outputSize}
+ \end{array}
+ \end{equation*}
+ %
+ \emph{Accessor Functions}
+ %
+ \begin{center}
+ \fun{adaPerUTxOByte},
+ \fun{outputSizeConstants}
+ \end{center}
+ %
+ \caption{Definitions Used in Protocol Parameters}
+ \label{fig:defs:protocol-parameters}
+\end{figure*}
+
@@ -178,7 +178,8 @@
 \newcommand{\RdmrsHash}{\type{RdmrsHash}}
 \newcommand{\Script}{\type{Script}}
 \newcommand{\ScriptPlutus}{\type{Script}_{plc}}
-\newcommand{\ScriptMPS}{\type{Script}_{fps}}
+\newcommand{\ScriptNI}{\type{Script^{native}_{v1}}}
+\newcommand{\ScriptMPS}{\type{Script^{native}_{v2}}}
 \newcommand{\ScriptMSig}{\type{Script}_{msig}}
 \newcommand{\ScriptV}{\type{Script_{v}}}
 \newcommand{\Datum}{\type{Datum}}
@@ -359,6 +360,7 @@
 \include{introduction}
 \include{notation}
 \include{value}
+\include{protocol-parameters}
 \include{transactions}
 
 \include{utxo}

@@ -4,8 +4,8 @@
  %
  \begin{equation*}
  \begin{array}{r@{~\in~}l@{\qquad=\qquad}lr}
- \var{s_{fps}} & \ScriptMPS & \text{extended script language}
- \\
+ \var{s_{v1}} & \ScriptNI & \ScriptMSig \\
+ \var{s_{v2}} & \ScriptMPS & \text{extended script language}
  \end{array}
  \end{equation*}
  %
@@ -15,7 +15,7 @@
  \begin{array}{r@{~\in~}l@{\qquad=\qquad}lr}
  \var{txout} & \TxOut & \Addr \times \hldiff{\Value} \\
 % & \text{tx outputs}
- \var{s} & \Script & \hldiff{\ScriptMSig \uniondistinct \ScriptMPS}
+ \var{s} & \Script & \hldiff{\ScriptNI \uniondistinct \ScriptMPS}
 % & \text{scripts}
  \\
  \end{array}
@@ -31,9 +31,9 @@
  & \times~ \seqof{\DCert} & \fun{txcerts}& \text{certificates}\\
  & \times ~\hldiff{\Value} & \hldiff{\fun{forge}} &\text{value forged}\\
  & \times ~\Coin & \fun{txfee} &\text{non-script fee}\\
- & \times ~\hldiff{\Slot^? \times \Slot^?} & \fun{txvldt} & \text{validity interval}\\
+ & \times ~\hldiff{\Slot^? \times \Slot^?} & \hldiff{\fun{txvldt}} & \text{validity interval}\\
  & \times~ \Wdrl & \fun{txwdrls} &\text{reward withdrawals}\\
- & \times ~\Update & \fun{txUpdates} & \text{update proposals}\\
+ & \times ~\Update^? & \fun{txUpdates} & \text{update proposals}\\
  & \times ~\MetaDataHash^? & \fun{txMDhash} & \text{metadata hash}
  \end{array}
  \end{equation*}
@@ -66,13 +66,14 @@ \subsection*{New Output Type}
 
 \subsection*{New Script Type}
 
-The type $\Script$ has been extended to include a new scripting language,
+The multi-signature scripting language has been renamed to $\ScriptNI$ and
+the type $\Script$ has been extended to include a new scripting language,
 $\ScriptMPS$. The two types of scripts which make up the $\Script$ type are both
 native, meaning
 that they are evaluated by the ledger directly. We specify the evaluation
 function for the additional script type in section~\ref{sec:mps-lang}.
 
-Both types of scripts can be used in the exact same way, which means, for this
+Both types of scripts can be used for the same purposes, which means, for this
 spec, as
 
 \begin{itemize}

@@ -119,7 +119,7 @@ \subsection*{The UTXO Transition Rule}
  \item The transaction is not forging any Ada.
 
  \item The $\Value$ of each output is constrained from below by a
- $\Value$ that contains the product of $\var{minUTxOValue}$ and the
+ $\Value$ that contains the product of $\var{adaPerUTxOByte}$ and the
  estimated size of the output as Ada, and zero otherwise. Note that
  this implies that no quantity appearing in that output can be
  negative.
@@ -155,10 +155,10 @@ \subsection*{The UTXO Transition Rule}
  \\
  ~
  \\
- \hldiff{\mathsf{adaPolicy}~\notin \supp{\fun{forge}~tx}} \\
+ \hldiff{\mathsf{adaPolicy}~\notin \supp{\fun{forge}~txb}} \\
  ~\\
  \hldiff{\forall txout \in \txouts{txb},} \\
- \hldiff{txout \geq \fun{coinToValue}(\fun{outputSize}~{txout} * \fun{minUTxOValue}~pp)} \\~
+ \hldiff{txout \geq \fun{coinToValue}(\fun{outputSize}~{txout} * \fun{adaPerUTxOByte}~pp)} \\~
  \\
  \forall (\wcard\mapsto (a,~\wcard)) \in \txouts{txb}, \fun{netId}~a =\NetworkId
  \\
@@ -241,11 +241,3 @@ \subsection*{Witnessing}
 (forging, output-locking, etc.).
 All scripts are run in the same way, with $\fun{validateScript}$ being responsible
 for calling the evaluator appropriate for the specific type of script.
-
-\begin{note}
- The cost model for the new script type is non-existent, the bigger scripts
- cost more only because they increase the size of the transaction.
-
- This could be a problem with arbitrary ORs! Checking lots of things before
- concluding the script fails could be bad
-\end{note}
@@ -18,10 +18,12 @@ \section{Output Size}
 
 \begin{figure*}[h]
  \begin{align*}
- & \fun{outputSize} \in \TxOut \to \MemoryEstimate \\
- & \fun{outputSize} ~\var{out} = k_0 + k_1 * |\{ (\var{pid}, \var{aid}) : \var{v}~\var{pid}~\var{aid} \neq 0
+ & \fun{outputSize} \in \PParams \to \TxOut \to \MemoryEstimate \\
+ & \fun{outputSize}~{pp}~\var{out} = k_0 + k_1 * |\{ (\var{pid}, \var{aid}) : \var{v}~\var{pid}~\var{aid} \neq 0
  \land (\var{pid}, \var{aid}) \neq (\mathsf{adaPolicy}, \mathsf{adaName}) \}| \\
- & \phantom{\fun{outputSize} ~\var{out} = k_0} + k_2 * |\{ \var{pid} : \exists aid : v~pid~aid \neq 0 \}|
+ & \phantom{\fun{outputSize}~{pp}~\var{out} = k_0} + k_2 * |\{ \var{pid} : \exists aid : v~pid~aid \neq 0 \}| \\
+ & ~~\where \\
+ & ~~~~~~(k_0, k_1, k_2) = \fun{outputSizeConstants}~{pp}
  \end{align*}
  \caption{Value Size}
  \label{fig:test}

@@ -35,7 +35,7 @@ \section{Coin and Multi-Asset Tokens}
  %
  \begin{align*}
  \mathsf{adaPolicy} \in& ~\PolicyID & \text{Ada Policy ID} \\
- \mathsf{adaName} \in& ~\AssetName & \text{Ada Asset Name} \\
+ \mathsf{adaName} \in& ~\AssetName & \text{Ada Asset Name}
  \end{align*}
  \emph{Helper Functions}
  %
@@ -86,6 +86,8 @@ \subsection*{Representing Multi-asset Types and Values}
  \emph{token bundles}.
 
  \item $\mathsf{adaPolicy}$ and $\mathsf{adaName}$ are the $\PolicyID$ and $\AssetName$ of Ada respectively.
+ It is not possible to forge any token with the $\PolicyID$ $\mathsf{adaPolicy}$, which means that every
+ token in the UTxO belonging to $\mathsf{adaPolicy}$ will have $\AssetName$ $\mathsf{adaName}$.
 
  \item $\fun{coinToValue}$ and $\fun{valueToCoin}$ convert between the two types,
  by taking a $\Coin$ to a $\Value$ that only contains Ada, and extracting the amount of Ada from a $\Value$ respectively.