diff --git a/docs/workshop/0-introduction/d4-introduction.tex b/docs/workshop/0-introduction/d4-introduction.tex
index e48ada4..773a070 100644
--- a/docs/workshop/0-introduction/d4-introduction.tex
+++ b/docs/workshop/0-introduction/d4-introduction.tex
@@ -189,6 +189,11 @@ After the stream is processed depending of the type using dedicated worker.
         \end{itemize}
 \end{frame}
 
+\begin{frame}
+        \frametitle{D4 server - type 254 - implementation}
+        \includegraphics[scale=0.3]{d4-worker-2.png}
+\end{frame}
+
 \begin{frame}
         \frametitle{D4 server - management interface}
 The D4 server provides a web interface to manage D4 sensors, sessions and analyzer.
diff --git a/docs/workshop/0-introduction/d4-worker-2.png b/docs/workshop/0-introduction/d4-worker-2.png
new file mode 100644
index 0000000..3ca0410
Binary files /dev/null and b/docs/workshop/0-introduction/d4-worker-2.png differ