diff --git a/doc/MCD.svg b/doc/MCD.svg
new file mode 100644
index 0000000..68875fa
--- /dev/null
+++ b/doc/MCD.svg
@@ -0,0 +1,136 @@
+<?xml version="1.0" encoding="utf-8"?>
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+<rect id="frame" x="0" y="0" width="354" height="338" fill="#fff" stroke="none" stroke-width="0"/>
+
+<!-- Association CHAT -->
+<g class="page_0_x0FZqot8 diagram_page" visibility="visible">
+	<path d="M181 169 C138.33 123.67 138.33 84.33 181 51" fill="none" stroke="#878787" stroke-width="2"/>
+	<text x="155" y="110" fill="#b2182b" font-family="Verdana" font-size="12">0,N</text>
+	<path d="M181 169 C223.67 123.67 223.67 84.33 181 51" fill="none" stroke="#878787" stroke-width="2"/>
+	<text x="185" y="110" fill="#b2182b" font-family="Verdana" font-size="12" onmouseover="show(evt,'mère')" onmouseout="hide(evt)" style="cursor: pointer;">0,N</text>
+	<polygon points="211.61 118.0 208.32 105.0 213.32 110.19 220.04 107.57" fill="#878787" stroke-width="0"/>
+	<line x1="306" y1="51" x2="181" y2="51" stroke="#878787" stroke-width="2"/>
+	<text x="241" y="68" fill="#b2182b" font-family="Verdana" font-size="12">1,1</text>
+	<g>
+		<path d="M191 26 a14 14 90 0 1 14 14 V51 h-48 V40 a14 14 90 0 1 14 -14" fill="#bababa" stroke="#bababa" stroke-width="0"/>
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+		<rect x="157" y="26" width="48" height="50" fill="none" rx="14" stroke="#878787" stroke-width="2"/>
+		<line x1="157" y1="51" x2="205" y2="51" stroke="#878787" stroke-width="1"/>
+		<text x="164" y="43.75" fill="#000" font-family="Verdana" font-size="12">CHAT</text>
+	</g>
+</g>
+
+<!-- Association WIN -->
+<g class="page_0_x0FZqot8 diagram_page" visibility="visible">
+	<line x1="67" y1="287" x2="67" y2="169" stroke="#878787" stroke-width="2"/>
+	<text x="72" y="237" fill="#b2182b" font-family="Verdana" font-size="12">1,1</text>
+	<line x1="181" y1="169" x2="67" y2="169" stroke="#878787" stroke-width="2"/>
+	<text x="97" y="186" fill="#b2182b" font-family="Verdana" font-size="12">0,N</text>
+	<g>
+		<path d="M74 144 a14 14 90 0 1 14 14 V169 h-42 V158 a14 14 90 0 1 14 -14" fill="#bababa" stroke="#bababa" stroke-width="0"/>
+		<path d="M88 169 v11 a14 14 90 0 1 -14 14 H60 a14 14 90 0 1 -14 -14 V169 H42" fill="#e0e0e0" stroke="#e0e0e0" stroke-width="0"/>
+		<rect x="46" y="144" width="42" height="50" fill="none" rx="14" stroke="#878787" stroke-width="2"/>
+		<line x1="46" y1="169" x2="88" y2="169" stroke="#878787" stroke-width="1"/>
+		<text x="54" y="161.75" fill="#000" font-family="Verdana" font-size="12">WIN</text>
+	</g>
+</g>
+
+<!-- Association POSSESS -->
+<g class="page_0_x0FZqot8 diagram_page" visibility="visible">
+	<line x1="181" y1="169" x2="306" y2="169" stroke="#878787" stroke-width="2"/>
+	<text x="243" y="186" fill="#b2182b" font-family="Verdana" font-size="12">0,N</text>
+	<line x1="306" y1="51" x2="306" y2="169" stroke="#878787" stroke-width="2"/>
+	<text x="311" y="110" fill="#b2182b" font-family="Verdana" font-size="12">1,1</text>
+	<g>
+		<path d="M328 144 a14 14 90 0 1 14 14 V169 h-72 V158 a14 14 90 0 1 14 -14" fill="#bababa" stroke="#bababa" stroke-width="0"/>
+		<path d="M342 169 v11 a14 14 90 0 1 -14 14 H284 a14 14 90 0 1 -14 -14 V169 H72" fill="#e0e0e0" stroke="#e0e0e0" stroke-width="0"/>
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+		<line x1="270" y1="169" x2="342" y2="169" stroke="#878787" stroke-width="1"/>
+		<text x="277" y="161.75" fill="#000" font-family="Verdana" font-size="12">POSSESS</text>
+	</g>
+</g>
+
+<!-- Association LOSE -->
+<g class="page_0_x0FZqot8 diagram_page" visibility="visible">
+	<line x1="67" y1="287" x2="181" y2="287" stroke="#878787" stroke-width="2"/>
+	<text x="130" y="304" fill="#b2182b" font-family="Verdana" font-size="12">1,1</text>
+	<line x1="181" y1="169" x2="181" y2="287" stroke="#878787" stroke-width="2"/>
+	<text x="186" y="237" fill="#b2182b" font-family="Verdana" font-size="12">0,N</text>
+	<g>
+		<path d="M191 262 a14 14 90 0 1 14 14 V287 h-48 V276 a14 14 90 0 1 14 -14" fill="#bababa" stroke="#bababa" stroke-width="0"/>
+		<path d="M205 287 v11 a14 14 90 0 1 -14 14 H171 a14 14 90 0 1 -14 -14 V287 H48" fill="#e0e0e0" stroke="#e0e0e0" stroke-width="0"/>
+		<rect x="157" y="262" width="48" height="50" fill="none" rx="14" stroke="#878787" stroke-width="2"/>
+		<line x1="157" y1="287" x2="205" y2="287" stroke="#878787" stroke-width="1"/>
+		<text x="165" y="279.75" fill="#000" font-family="Verdana" font-size="12">LOSE</text>
+	</g>
+</g>
+
+<!-- Entity MESSAGE -->
+<g class="page_0_x0FZqot8 diagram_page" visibility="visible">
+	<g>
+		<rect x="267" y="9" width="78" height="25" fill="#f4a582" stroke="#f4a582" stroke-width="0" opacity="1"/>
+		<rect x="267" y="34" width="78" height="59" fill="#fddbc7" stroke="#fddbc7" stroke-width="0" opacity="1"/>
+		<rect x="267" y="9" width="78" height="84" fill="none" stroke="#d6604d" stroke-width="2" opacity="1"/>
+		<line x1="267" y1="34" x2="345" y2="34" stroke="#d6604d" stroke-width="1"/>
+	</g>
+	<text x="276" y="26.75" fill="#000" font-family="Verdana" font-size="12">MESSAGE</text>
+	<text x="272" y="51.8" fill="#000" font-family="Verdana" font-size="12">messageId</text>
+	<line x1="272" y1="54" x2="339" y2="54" stroke="#000" stroke-width="1"/>
+	<text x="272" y="68.8" fill="#000" font-family="Verdana" font-size="12">message</text>
+	<text x="272" y="85.8" fill="#000" font-family="Verdana" font-size="12">timestamp</text>
+</g>
+
+<!-- Entity PLAYER -->
+<g class="page_0_x0FZqot8 diagram_page" visibility="visible">
+	<g>
+		<rect x="124" y="118" width="114" height="25" fill="#f4a582" stroke="#f4a582" stroke-width="0" opacity="1"/>
+		<rect x="124" y="143" width="114" height="77" fill="#fddbc7" stroke="#fddbc7" stroke-width="0" opacity="1"/>
+		<rect x="124" y="118" width="114" height="102" fill="none" stroke="#d6604d" stroke-width="2" opacity="1"/>
+		<line x1="124" y1="143" x2="238" y2="143" stroke="#d6604d" stroke-width="1"/>
+	</g>
+	<text x="158" y="135.75" fill="#000" font-family="Verdana" font-size="12">PLAYER</text>
+	<text x="129" y="160.8" fill="#000" font-family="Verdana" font-size="12">playerId</text>
+	<line x1="129" y1="163" x2="180" y2="163" stroke="#000" stroke-width="1"/>
+	<text x="129" y="177.8" fill="#000" font-family="Verdana" font-size="12">name</text>
+	<text x="129" y="194.8" fill="#000" font-family="Verdana" font-size="12">nbBallTouchTotal</text>
+	<text x="129" y="211.8" fill="#000" font-family="Verdana" font-size="12">timePlayed</text>
+</g>
+
+<!-- Entity GAME -->
+<g class="page_0_x0FZqot8 diagram_page" visibility="visible">
+	<g>
+		<rect x="9" y="245" width="116" height="25" fill="#f4a582" stroke="#f4a582" stroke-width="0" opacity="1"/>
+		<rect x="9" y="270" width="116" height="59" fill="#fddbc7" stroke="#fddbc7" stroke-width="0" opacity="1"/>
+		<rect x="9" y="245" width="116" height="84" fill="none" stroke="#d6604d" stroke-width="2" opacity="1"/>
+		<line x1="9" y1="270" x2="125" y2="270" stroke="#d6604d" stroke-width="1"/>
+	</g>
+	<text x="49" y="262.75" fill="#000" font-family="Verdana" font-size="12">GAME</text>
+	<text x="14" y="287.8" fill="#000" font-family="Verdana" font-size="12">gameId</text>
+	<line x1="14" y1="290" x2="61" y2="290" stroke="#000" stroke-width="1"/>
+	<text x="14" y="304.8" fill="#000" font-family="Verdana" font-size="12">durationGame</text>
+	<text x="14" y="321.8" fill="#000" font-family="Verdana" font-size="12">nbMaxExchanges</text>
+</g>
+
+<!-- Notes -->
+<script type="text/ecmascript">
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+		note.textContent = text;
+		note.setAttributeNS(null, "visibility", "visible");
+		document.getElementById(pos + "_overlay_x0FZqot8").setAttributeNS(null, "visibility", "visible");
+	}
+	function hide(evt) {
+		document.getElementById("top_note_x0FZqot8").setAttributeNS(null, "visibility", "hidden");
+		document.getElementById("top_overlay_x0FZqot8").setAttributeNS(null, "visibility", "hidden");
+		document.getElementById("bottom_note_x0FZqot8").setAttributeNS(null, "visibility", "hidden");
+		document.getElementById("bottom_overlay_x0FZqot8").setAttributeNS(null, "visibility", "hidden");
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+</svg>
\ No newline at end of file