presentation: progress

7 files changed, 221 insertions, 157 deletions

diff --git a/.gitignore b/.gitignore
index 1d69ca7..0512646 100644
--- a/.gitignore
+++ b/.gitignore
@@ -4,4 +4,4 @@ log
 /docs/*
 !/docs/*.docx
 !/docs/*.tex
-!/docs/*.png
\ No newline at end of file
+!/docs/media
\ No newline at end of file
diff --git a/docs/fee.png b/docs/media/fee.png
index 283c286..283c286 100644
--- a/docs/fee.png
+++ b/docs/media/fee.png
diff --git a/docs/media/news0.png b/docs/media/news0.png
new file mode 100644
index 0000000..d1f5ab7
--- /dev/null
+++ b/docs/media/news0.png
diff --git a/docs/media/news1.png b/docs/media/news1.png
new file mode 100644
index 0000000..c567581
--- /dev/null
+++ b/docs/media/news1.png
diff --git a/docs/media/news2.png b/docs/media/news2.png
new file mode 100644
index 0000000..f33c1ba
--- /dev/null
+++ b/docs/media/news2.png
diff --git a/docs/taler.png b/docs/media/taler.png
index 503ae20..503ae20 100644
--- a/docs/taler.png
+++ b/docs/media/taler.png
diff --git a/docs/presentation.tex b/docs/presentation.tex
index 0d6cb8b..2e9cd3b 100644
--- a/docs/presentation.tex
+++ b/docs/presentation.tex
@@ -12,7 +12,7 @@
 \author{Antoine d'Aligny}
 \institute{Bern University of Applied Sciences}
 \date{\today}
-\titlegraphic{\includegraphics[width=2.5cm]{taler.png}} 
+\titlegraphic{\includegraphics[width=2.5cm]{media/taler.png}} 
 
 \begin{document}
 
@@ -20,137 +20,209 @@
     \titlepage
 \end{frame}
 
-\begin{frame}{Outline}
-    \tableofcontents
-\end{frame}
-
-\section{Introduction}
-
-\begin{frame}{Introduction}
+\begin{frame}{Blockchain based cryptocurrencies}
+    \begin{tikzpicture}[remember picture,overlay]
+        \node (N1)[above right=5mm and 25mm of current page.center] {\includegraphics[width=34mm]{media/news1.png}};
+        \node (N0)[below=-3mm of N1] {\includegraphics[width=34mm]{media/news0.png}};
+        \node (N2)[below left=-26mm and -2.5mm of N1] {\includegraphics[width=34mm]{media/news2.png}};
+    \end{tikzpicture}
     \begin{block}{Biggest cryptocurrencies}
         \begin{itemize}
             \item \textbf{BTC} Bitcoin
             \item \textbf{ETH} Ethereum
         \end{itemize}
     \end{block}
-
-    \begin{block}{Common blockchain limitation}
+    \begin{block}{Common blockchain limitations}
         \begin{itemize}
             \item \textbf{Delay} block and confirmation delay
             \item \textbf{Cost} transaction fees
             \item \textbf{Scalability} limited amount of transaction per second
             \item \textbf{Ecological impact} computation redundancy
             \item \textbf{Privacy}
+            \item \textbf{Regulatory risk}
         \end{itemize}
     \end{block}
 \end{frame}
 
-\section{Taler}
-
 \begin{frame}{Taler}{Architecture}
-    \begin{center}
+    \begin{columns}
+        \column{0.5\paperwidth}
         \begin{tikzpicture}[
                 rect/.style={circle, draw=black},
-                sym/.style={->, shorten >= 2pt, shorten <= 2pt}
+                sym/.style={-stealth, shorten >= 2pt, shorten <= 2pt}
             ]
+            % Taler payment system
             \node[rect](1) {Exchange};
-            \node[rect, below left=1.5cm and 0.7cm of 1](2) {Customer};
-            \node[rect, below right=1.5cm and 0.7cm of 1](3) {Merchant};
+            \node[rect,below left=1.5cm and 0.7cm of 1](2) {Customer};
+            \node[rect,below right=1.5cm and 0.7cm of 1](3) {Merchant};
 
             \draw[sym] (1) -- node [midway, above, sloped] {\tiny Withdraw coins} (2);
             \draw[sym] (2) -- node [midway, above, sloped] {\tiny Spend coins} (3);
             \draw[sym] (3) -- node [midway, above, sloped] {\tiny Deposit coins} (1);
 
+            % Settlement layer
             \node[left=2cm of 1](E1){};
             \node[right=2cm of 1](E2){};
             \draw[sym] (E1) -- node [midway, above] {\tiny Deposit money} (1);
             \draw[sym] (1) -- node [midway, above] {\tiny Withdraw money} (E2);
 
-
+            % Auditor
             \node[above= of 1](A){Auditor};
             \draw[sym] (A) -- node [midway, right] {\tiny Verify} (1);
-        \end{tikzpicture}
-    \end{center}
-\end{frame}
 
-\begin{frame}{Taler}{Coins - WIP}
-    \begin{itemize}
-        \item Blind signatures
-        \item Currency agnostic
-        \item Change signature every year, Forget previous transactions (Pruning)
-        \item Compatibility ?
-    \end{itemize}
+            % Separator
+            \node[below=1mm of E1] (S1S) {};
+            \node[below=1mm of E2] (S1E) {};
+            \node[above=6mm of E1] (S2S) {};
+            \node[above=6mm of E2] (S2E) {};
+
+            \draw[dotted] (S1S) -- (S1E);
+            \draw[dotted] (S2S) -- (S2E);
+
+            \node[below right=-2mm and -1.5mm of S2S] {\tiny{\emph{Settlement Layer}}};
+            \node[below right=-2mm and -1.5mm of S1S] {\tiny{\emph{Taler payment system}}};
+        \end{tikzpicture}
+        \column{0.47\paperwidth}
+        \begin{block}{Settlement layer}
+            \begin{itemize}
+                \item Blockchain?
+            \end{itemize}
+        \end{block}
+        \begin{block}{Taler payment system}
+            \begin{itemize}
+                \item Blind signatures (privacy)
+                \item Rotate keys every year. Forget previous transactions (Pruning)
+            \end{itemize}
+        \end{block}
+
+    \end{columns}
 \end{frame}
 
-\begin{frame}{Taler}{Off-chain transactions}
+\begin{frame}{Taler}{Blockchain settlement layer}
     \begin{center}
         \begin{tikzpicture}[
                 rect/.style={rectangle, draw=black, minimum width=28mm},
-                sym/.style={<->, shorten >= 2pt, shorten <= 2pt},
+                sym/.style={stealth-stealth, shorten >= 2pt, shorten <= 2pt},
                 block/.style={rectangle,draw=black,fill=black!10,minimum size=7mm},
             ]
 
             %% Architecture
-
             \node(Tt){Taler};
-            \node[rect, below=0cm of Tt](Tc){Exchange};
-            \node[rect, fit={(Tt) (Tc)}](T){};
+            \node[rect,below=0cm of Tt](Tc){Exchange};
+            \node[rect,fit={(Tt) (Tc)}](T){};
 
-            \node[rect, below=7mm of Tc](D) {Depolymerization};
+            \node[rect,below=7mm of Tc](D) {Depolymerization};
 
-            \node[rect, below=7mm of D](Bc){Node};
+            \node[rect,below=7mm of D](Bc){Node};
             \node[below=0cm of Bc](Bt){Blockchain};
-            \node[rect, fit={(Bt) (Bc)}](B){};
+            \node[rect,fit={(Bt) (Bc)}](B){};
 
             \draw[sym] (T) -- (D);
             \draw[sym] (D) -- (B);
 
             %% Blockchain
-            \node[block,right=7mm of B] (1){};
+            \node[block,right=8mm of B] (1){};
             \node[block,right=4mm of 1] (2){};
             \node[block,right=4mm of 2] (3){};
             \node[block,right=4mm of 3] (4){};
             \node[block,right=4mm of 4] (5){};
             \node[block,right=4mm of 5] (6){};
-            \draw[->] (1) -- (2);
-            \draw[->] (2) -- (3);
-            \draw[->] (3) -- (4);
-            \draw[->] (4) -- (5);
-            \draw[->] (5) -- (6);
+            \draw[-stealth] (1) -- (2);
+            \draw[-stealth] (2) -- (3);
+            \draw[-stealth] (3) -- (4);
+            \draw[-stealth] (4) -- (5);
+            \draw[-stealth] (5) -- (6);
 
-            %% Taler
-            \node[block, right=18mm of T] (off){Off-chain transactions};
+            \node[left=4mm of 1] (S){};
+            \node[right=4mm of 6] (E){};
+            \draw[-stealth] (S) -- (1);
+            \draw[-stealth] (6) -- (E);
 
-            % Depolymerization
-            \node[right=11mm of D] {\small{Deposit}};
-            \node[right=49mm of D] {\small{Withdraw}};
-            \draw[dashed,->] (1.north) |- (off.west);
-            \draw[dashed,->] (off.east) -| (6.north);
+            %% Taler
+            \node[block, below right=-7.5mm and 20.5mm of T] (off){Off-chain transactions};
+            \node[above=-0.5mm of off] {\includegraphics[height=7mm]{media/taler.png}};
+
+            %% Depolymerization
+            \node[right=12mm of D] {\small{Deposit}};
+            \node[right=50mm of D] {\small{Withdraw}};
+            \draw[dashed,-stealth] (1.north) |- (off.west);
+            \draw[dashed,-stealth] (off.east) -| (6.north);
         \end{tikzpicture}
     \end{center}
 \end{frame}
 
-\section{Depolymerization}
+\begin{frame}{Challenges}
+    \begin{block}{Taler Metadata}
+        \begin{itemize}
+            \item Metadata are required to link a wallet to its deposits and withdraws
+            \item Putting metadata in blockchain transactions can be tricky
+            \item The whole on-chain transaction history can be retrieved from
+                  the blockchain. \textbf{Easily auditable}
+        \end{itemize}
+    \end{block}
+    \begin{block}{Blockchain based cryptocurrencies}
+        \begin{itemize}
+            \item Reorganisation resilient
+            \item Adaptive confirmation
+            \item Resolve stuck transactions
+        \end{itemize}
+    \end{block}
+\end{frame}
 
-\begin{frame}{Depolymerization}{Metadata}
-    \begin{itemize}
-        \item Metadata are stored in depolymerizer on-chain transactions
-        \item The whole on-chain transaction history can be retrieved from the blockchain
-        \item \textbf{Easily auditable}
-    \end{itemize}
+\begin{frame}{Challenges}{Chain reorganisation}
+    \begin{center}
+        \begin{tikzpicture}[
+                block/.style={rectangle,draw=black,fill=black!10,minimum size=7mm},
+                ar/.style={-stealth}
+            ]
+            % Common
+            \node[block](1){};
+            \node[block,right=5mm of 1](2){$D_0$};
+            \node[block,right=5mm of 2](3){};
+            \draw[ar] (1) -- (2);
+            \draw[ar] (2) -- (3);
+
+            % Current
+            \node [block,right=5mm of 3](4){};
+            \node[block,right=5mm of 4](5){};
+            \node[block,right=5mm of 5](6){$D_1$};
+            \draw[ar] (3) -- (4);
+            \draw[ar] (4) -- (5);
+            \draw[ar] (5) -- (6);
+
+            % Fork
+            \node [block,above=7mm of 4](4p){};
+            \node[block,right=5mm of 4p](5p){$D_2$};
+            \node[block,right=5mm of 5p](6p){};
+            \node[block,right=5mm of 6p](7p){};
+            \draw[ar] (3.east) -- (4p.west);
+            \draw[ar] (4p) -- (5p);
+            \draw[ar] (5p) -- (6p);
+            \draw[ar] (6p) -- (7p);
+
+            % Indication
+            \node [right=5mm of 7p]{\emph{fork}};
+            \node [right=17mm of 6]{\emph{active}};
+        \end{tikzpicture}
+    \end{center}
+    A fork is when concurrent blockchain states coexist. Nodes will follow
+    the longest chain, replacing recent blocks if necessary. That is a
+    blockchain reorganisation. Taler expects deposit transactions to be
+    consistent. If a deposit transaction disappears from the blockchain,
+    depolymerizer is comprised.
 \end{frame}
 
 \begin{frame}{Depolymerization}{Architecture}
     \begin{center}
         \begin{tikzpicture}[
                 rect/.style={rectangle, draw=black, minimum height=6mm, minimum width=28mm},
-                sym/.style={<->, shorten >= 2pt, shorten <= 2pt}
+                sym/.style={stealth-stealth, shorten >= 2pt, shorten <= 2pt}
             ]
             \node[rect](1) {Taler Exchange};
-            \node[rect,below=of 1](2) {wire\_gateway};
+            \node[rect,below=of 1](2) {Wire Gateway};
             \node[rect,right=of 2](3) {PostgreSQL};
-            \node[rect,right=of 3](4) {\#\#\#\_wire};
-            \node[rect,above=of 4](5) {Full Node};
+            \node[rect,right=of 3](4) {DLT Wire};
+            \node[rect,above=of 4](5) {DLT Full Node};
 
             \draw[sym] (1) -- node [midway,right] {\tiny HTTP} (2);
             \draw[sym] (2) -- node [midway,above] {\tiny SQL} (3);
@@ -158,16 +230,45 @@
             \draw[sym] (4) -- node [midway,left ] {\tiny RPC} (5);
 
 
+            \node[above= 2mm of 1]{\small{\emph{Wire Gateway API}}};
+            \node[above= 2mm of 5]{\small{\emph{DLT specific}}};
+            \node[above=22mm of 3](T) {};
+            \draw[dotted] (3) -- (T);
         \end{tikzpicture}
     \end{center}
-    Two processes sharing a common database for state and communication.
-    wire\_gateway is currency agnostic and there is a specific wire binary for
-    every supported currency.
+    \begin{itemize}
+        \item Common database to store transactions state and communicate
+              with notifications
+        \item Wire Gateway for Taler API compatibility
+        \item Specific wire for DLT compatibility
+    \end{itemize}
 \end{frame}
 
-\section{btc-wire}
+\begin{frame}{Depolymerization}{Metadata}
+    \begin{block}{Bitcoin - Withdraw}
+        \begin{itemize}
+            \item Transaction from code
+            \item Only 32B + URI
+            \item \textbf{OP\_RETURN}
+        \end{itemize}
+    \end{block}
+    \begin{block}{Bitcoin - Deposit}
+        \begin{itemize}
+            \item Transaction from common wallet software
+            \item Only 32B
+            \item \textbf{Fake Segwit Addresses}
+        \end{itemize}
+    \end{block}
+    \begin{block}{Ethereum - Withdraw and Deposit}
+        \begin{itemize}
+            \item Smart contract is the recommend way
+            \item Expensive and error prone (bigger attack surface)
+            \item \textbf{Custom contract input format}
+        \end{itemize}
+    \end{block}
+\end{frame}
 
-\begin{frame}{btc-wire}{Architecture}
+\begin{frame}{Depolymerization}{Architecture}
     \begin{center}
         \begin{tikzpicture}[
                 rect/.style={rectangle, draw=black, minimum height=6mm, minimum width=38mm},
@@ -177,15 +278,15 @@
             \node(wat) {Watcher};
             \node[rect, below=1mm of wat](wa1) {Wait for new block};
             \node[rect, below=4mm of wa1](wa2) {Notify new block};
-            \draw[->] (wa1) -- (wa2);
-            \draw[->] (wa2) .. controls ([xshift=-0.3cm] wa2.west) and ([xshift=-0.3cm] wa1.west) .. (wa1);
+            \draw[-stealth] (wa1) -- (wa2);
+            \draw[-stealth] (wa2) .. controls ([xshift=-0.3cm] wa2.west) and ([xshift=-0.3cm] wa1.west) .. (wa1);
 
             % Analysis loop
             \node[below=5mm of wa2] (at) {Analysis};
             \node[rect, below=1mm of at](a1) {Wait for notification};
             \node[rect, below=4mm of a1](a2) {Analyse};
-            \draw[->] (a1) -- (a2);
-            \draw[->] (a2) .. controls ([xshift=-0.3cm] a2.west) and ([xshift=-0.3cm] a1.west) .. (a1);
+            \draw[-stealth] (a1) -- (a2);
+            \draw[-stealth] (a2) .. controls ([xshift=-0.3cm] a2.west) and ([xshift=-0.3cm] a1.west) .. (a1);
 
             % Worker loop
             \node[rect, below right= -2mm and 1cm of wa1](wo1) {Wait for notification};
@@ -193,134 +294,98 @@
             \node[rect, below=4mm of wo2](wo3) {Send};
             \node[rect, below=4mm of wo3](wo4) {Bounce};
             \node[above=1mm of wo1]{Worker};
-            \draw[->] (wo1) -- (wo2);
-            \draw[->] (wo2) -- (wo3);
-            \draw[->] (wo3) -- (wo4);
-            \draw[->] (wo4) .. controls ([xshift=-0.4cm] wo4.west) and ([xshift=-0.4cm] wo1.west) .. (wo1);
+            \draw[-stealth] (wo1) -- (wo2);
+            \draw[-stealth] (wo2) -- (wo3);
+            \draw[-stealth] (wo3) -- (wo4);
+            \draw[-stealth] (wo4) .. controls ([xshift=-0.4cm] wo4.west) and ([xshift=-0.4cm] wo1.west) .. (wo1);
         \end{tikzpicture}
     \end{center}
     \centering
     Three concurrent loops
 \end{frame}
 
-\begin{frame}{btc-wire}{Metadata}
-    \begin{block}{Withdraw}
-        \begin{itemize}
-            \item Transaction from code
-            \item Only 32B + URI
-            \item \textbf{OP\_RETURN}
-        \end{itemize}
-    \end{block}
-    \begin{block}{Deposit}
-        \begin{itemize}
-            \item Transaction from common wallet software
-            \item Only 32B
-            \item \textbf{Fake Segwit Addresses}
-        \end{itemize}
-    \end{block}
-\end{frame}
-
-
-\begin{frame}{btc-wire}{Security features}
-    \begin{itemize}
-        \item Reorg resilient
-        \item Adaptive confirmation
-        \item Resolve stuck transaction
-    \end{itemize}
-\end{frame}
-
-\begin{frame}{btc-wire}{Reorg resilient}
+\begin{frame}{Reorganisation resilient}
     \begin{center}
         \begin{tikzpicture}[
                 block/.style={rectangle,draw=black,fill=black!10,minimum size=7mm},
                 conf/.style={draw=black!60!green,fill=black!60!green!10},
                 err/.style={draw=black!60!red,fill=black!60!red!10},
+                ar/.style={-stealth}
             ]
             % Common
-            \only<1>{
-                \node [block](1){};
-                \node [block,right=5mm of 1](2){$D_0$};
-                \node [block,right=5mm of 2](3){};
-            }
-            \only<2->{
-                \node [block,conf](1){};
-                \node [block,conf,right=5mm of 1](2){$D_0$};
-                \node [block,conf,right=5mm of 2](3){};
-            }
-            \draw[->] (1) -- (2);
-            \draw[->] (2) -- (3);
+            \node[block,conf](1){};
+            \node[block,conf,right=5mm of 1](2){$D_0$};
+            \node[block,conf,right=5mm of 2](3){};
+            \draw[ar] (1) -- (2);
+            \draw[ar] (2) -- (3);
 
             % Current
-            \only<1-2>{
+            \only<1>{
                 \node [block,right=5mm of 3](4){};
             }
-            \only<3->{
-                \node [block,conf,right=5mm of 3](4){\only<4>{$D_3$}};
+            \only<2->{
+                \node [block,conf,right=5mm of 3](4){\only<3>{$D_3$}};
             }
-            \node [block,right=5mm of 4](5){};
-            \node [block,right=5mm of 5](6){$D_1$};
-            \draw[->] (3) -- (4);
-            \draw[->] (4) -- (5);
-            \draw[->] (5) -- (6);
+            \node[block,right=5mm of 4](5){};
+            \node[block,right=5mm of 5](6){$D_1$};
+            \draw[ar] (3) -- (4);
+            \draw[ar] (4) -- (5);
+            \draw[ar] (5) -- (6);
 
             % Fork
-            \only<-3>{
+            \only<-2>{
                 \node [block,above=7mm of 4](4p){};
             }
-            \only<4>{
+            \only<3>{
                 \node [block,err,above=7mm of 4](4p){$D_3'$};
             }
-            \node [block,right=5mm of 4p](5p){$D_2$};
-            \node [block,right=5mm of 5p](6p){};
-            \node [block,right=5mm of 6p](7p){};
-            \draw[->] (3.east) -- (4p.west);
-            \draw[->] (4p) -- (5p);
-            \draw[->] (5p) -- (6p);
-            \draw[->] (6p) -- (7p);
+            \node[block,right=5mm of 4p](5p){$D_2$};
+            \node[block,right=5mm of 5p](6p){};
+            \node[block,right=5mm of 6p](7p){};
+            \draw[ar] (3.east) -- (4p.west);
+            \draw[ar] (4p) -- (5p);
+            \draw[ar] (5p) -- (6p);
+            \draw[ar] (6p) -- (7p);
 
             % Indication
             \node [right=5mm of 7p]{\emph{fork}};
             \node [right=17mm of 6]{\emph{active}};
         \end{tikzpicture}
     \end{center}
-    \only<1>{A fork is when concurrent blockchain states coexist. Nodes will
-        follow the longest chain, replacing recent blocks if necessary. That is a
-        blockchain reorganization. Taler expects deposit transactions to be
-        consistent. If a deposit transaction disappears from the blockchain btc-wire
-        is comprised.}
-    \only<2>{As small forks are common, we apply a confirmation delay to
-        handle the most common disturbances and attacks.}
-    \only<3>{If a reorganization longer than the confirmation delay happens,
+    \only<1>{As small reorganisations are common, we apply a confirmation delay
+        to handle the most common disturbances and attacks.}
+    \only<2>{If a reorganisation longer than the confirmation delay happens,
         but it does not remove deposits, btc-wire is safe.}
-    \only<4>{If it removed a confirmed deposit a powerful attacker may have
+    \only<3>{If it removed a confirmed deposit a powerful attacker may have
         created a conflicting transaction. btc-wire suspends operation until
         lost deposits reappear.}
 \end{frame}
 
-\begin{frame}{btc-wire}{Adaptive confirmation}
+\begin{frame}{Adaptive confirmation}
     \begin{center}
         \begin{tikzpicture}[
                 block/.style={rectangle,draw=black,fill=black!10,minimum size=7mm},
                 conf/.style={draw=black!60!green,fill=black!60!green!10},
                 conft/.style={text=black!60!green},
                 confl/.style={draw=black!60!green},
+                ar/.style={-stealth}
             ]
             % Common
             \node(0){};
             \node[block,conf,right=5mm of 0](1){};
             \node[block,conf,right=5mm of 1](2){};
-            \draw[->] (0) -- (1);
-            \draw[->] (1) -- (2);
+            \draw[ar] (0) -- (1);
+            \draw[ar] (1) -- (2);
 
             % Current
             \node[block,conf,right=5mm of 2](3){};
             \node[block,right=5mm of 3](4){};
             \node[block,right=5mm of 4](5){};
             \node[block,right=5mm of 5](6){};
-            \draw[->] (2) -- (3);
-            \draw[->] (3) -- (4);
-            \draw[->] (4) -- (5);
-            \draw[->] (5) -- (6);
+            \draw[ar] (2) -- (3);
+            \draw[ar] (3) -- (4);
+            \draw[ar] (4) -- (5);
+            \draw[ar] (5) -- (6);
 
             % Fork
             \node[block,above=7mm of 3](3p){};
@@ -328,11 +393,11 @@
             \node[block,right=5mm of 4p](5p){};
             \node[block,right=5mm of 5p](6p){};
             \node[block,right=5mm of 6p](7p){};
-            \draw[->] (2.east) -- (3p.west);
-            \draw[->] (3p) -- (4p);
-            \draw[->] (4p) -- (5p);
-            \draw[->] (5p) -- (6p);
-            \draw[->] (6p) -- (7p);
+            \draw[ar] (2.east) -- (3p.west);
+            \draw[ar] (3p) -- (4p);
+            \draw[ar] (4p) -- (5p);
+            \draw[ar] (5p) -- (6p);
+            \draw[ar] (6p) -- (7p);
 
             % Indication
             \node[right=5mm of 7p]{\emph{fork}};
@@ -351,12 +416,11 @@
         \end{tikzpicture}
     \end{center}
     If we experience a reorganisation once, its plausible for another one of the
-    same size to happen again. btc-wire learns from reorganizations by updating
+    same size to happen again. btc-wire learns from reorganisations by updating
     its confirmation time.
 \end{frame}
 
-
-\begin{frame}{btc-wire}{Handle stuck transactions}
+\begin{frame}{Handle stuck transactions}
     \begin{center}
         \begin{tikzpicture}[
                 dot/.style={circle,fill,inner sep=1pt,}
@@ -364,7 +428,7 @@
 
             % TODO caption with source (Ychart)
 
-            \node (I) {\includegraphics[width=\textwidth]{fee.png}};
+            \node (I) {\includegraphics[width=\textwidth]{media/fee.png}};
             \only<2->{
                 \node [below left=-2.5mm and -1.5cm of I] (Tx) {\small Tx};
                 \node [dot,above=8.4mm of Tx](D) {};
@@ -415,12 +479,12 @@
 \begin{frame}{Conclusion}
     \begin{itemize}
         \item [$-$] Trust exchange operator or auditors
-        \item [$+$] Fast and cheap, no blockchain
+        \item [$+$] Fast and cheap
         \item [$+$] Realtime, ms latency
-        \item [$+$] Scalability, close to 100k txs per second
+        \item [$+$] Linear scalability
         \item [$+$] Ecological
         \item [$+$] Privacy when it can, transparency when it must (avoid tax evasion and money laundering)
-        \item [$+$] Currency agnostic (payment system)
+        \item [$+$] Compatibility with blockchains
     \end{itemize}
 \end{frame}
 \end{document}
\ No newline at end of file