1 files changed, 46 insertions, 0 deletions
diff --git a/slides/2021-padsec/img/before.tex b/slides/2021-padsec/img/before.tex
new file mode 100644
index 0000000..f634ef4
--- /dev/null
+++ b/slides/2021-padsec/img/before.tex
@@ -0,0 +1,46 @@
+\begin{tikzpicture}[
+	-latex,
+	entity/.style = {
+		draw = gray!30,
+		thick,
+		rounded rectangle,
+		fill = white,
+		minimum width = 2cm,
+		font = \fontsize{8}{8}\selectfont,
+		text = white,
+	},
+	relation/.style = {
+		draw = none,
+		font = \fontsize{6}{6}\selectfont,
+	},
+	path/.style = {
+		draw,
+		thick,
+		-latex,
+	},
+]
+	\node[entity, fill=darkBlue] (Publisher) at (0,0) { Publisher };
+	\node[entity, fill=darkGreen, below=1.5cm of Publisher] (EndUser) {End-user};
+
+	% Key setup
+	\path[path, dashed] ($ (EndUser) + (2,0) $) --
+			node[relation, above] { Public key }
+		(EndUser);
+	% Get data and signature
+	\path[path] (Publisher) --
+			node[relation, right] {
+				\begin{tabular}{c}
+					Opaque data\\
+					Signature\\
+				\end{tabular}
+			}
+		(EndUser);
+	% Verification
+	\path[path, rounded corners]
+		(EndUser.180) -|
+		($ (EndUser) + (-1.25,-.75) $)
+			node[relation, below]{
+				Verify
+			} -|
+		(EndUser.210);
+\end{tikzpicture}