Cleanup, add stateful figure

doc/Design.tex

@@ -251,6 +251,12 @@ highest degree of flexibility, as it provides support for individual
 entries based on table entries and LPM table entries.
 % ----------------------------------------------------------------------
 \section{\label{design:statefulnat64}Stateful NAT64}
+\begin{figure}[h]
+  \includegraphics[scale=0.5]{p4switch-stateful}
+  \centering
+  \caption{Stateful NAT64 with P4}
+  \label{fig:p4switchstateful}
+\end{figure}
 Similar to stateless NAT64, the design of stateful NAT64 depends on
 the features of the individual implementation. As pointed out in section
 \ref{background:transition:statefulnat64}, stateful NAT64 is very
@@ -261,7 +267,9 @@ to solve this problem:
 \begin{itemize}
 \item For P4/BMV2 and P4/NetPFGA a python controller handles packets
   that don't have a table entry, sets the table entry in the P4 switch
-  and inserts the original packet afterwards back into the switch.
+  and inserts the original packet afterwards back into the
+  switch. Figure \ref{fig:p4switchstateful} shows the flow of a packet
+  with stateful translation in detail.
 \item With tayga we rely on the Linux kernel NAT44 capabilities
 \item Jool implements its own stateful mechanism based on port
   ranges

doc/graphviz/p4switch-stateful.dot

@@ -0,0 +1,59 @@
+digraph G {
+    rankdir="TB";
+
+    v4host [ shape="box" label="IPv4 Host" ];
+    v6host [ shape="box" label="IPv6 Host" ];
+    rank=same;
+
+
+    parser  [ label="Parser"];
+    deparser  [ label="Deparser"];
+    translation  [ label="Translation"];
+    mismatch  [ label="Table mismatch"];
+    v4packet  [ label="IPv6 Packet"];
+    v4packet2  [ label="IPv4 Packet"];
+    v6packet  [ label="IPv6 Packet"];
+    tableentry [ label="Create table entry" ];
+    tablematch [ label="Table match" ];
+
+    reinject [ label="Reinject packet" ];
+    controller [ label="Controller reads packet" ]
+
+    deparser  [ label="Deparser"];
+    deparser2  [ label="Deparser"];
+
+    subgraph cluster_nat64 {
+        label="P4 Switch";
+
+        parser;
+        v4packet;
+        deparser;
+        mismatch;
+        tablematch;
+        translation;
+        deparser2;
+
+    }
+
+    subgraph cluster_p4controller {
+        label="P4 Controller";
+
+        controller;
+        tableentry;
+        reinject;
+    }
+
+    v6host->v6packet->parser;
+    parser->v4packet;
+    v4packet->mismatch [ label="1." ];
+    mismatch->deparser->controller;
+    controller->tableentry->reinject;
+    reinject->parser;
+
+    v4packet->tablematch [ label="2." ];
+    tablematch->translation->deparser2;
+
+    deparser2->v4packet2->v4host;
+
+
+}