title: Not planned in rou.xml vehicles occur in SUMO while using veins
body: <p>I am using <strong>veins 3.0</strong>, with <strong>sumo0.21.0</strong> and <strong>omnetpp4.4</strong>.
  In the <em>name.rou.xml</em> I defined some vehicle types like this:</p>
  
  <pre><code>&lt;vType id="vtype0" accel="2.6" decel="6.6" sigma="0.5" length="2.5"  minGap="2.5" speedFactor="0.8" speedDev="0"  maxSpeed="88" color="1,1,0"/&gt;
  </code></pre>
  
  <p>I also defined flows:</p>
  
  <pre><code>   &lt;flow id="flow0" type="vtype6" route="B470" begin="0"  end="21599" period="3600"/&gt;
     &lt;flow id="flow1" type="vtype6" route="B470" begin="15"  end="604800" period="604800"/&gt;
     &lt;flow id="flow2" type="vtype6" route="B470" begin="30"  end="604800" period="604800"/&gt;
     &lt;flow id="flow3" type="vtype6" route="B470" begin="45"  end="604800" period="604800"/&gt;
     &lt;flow id="flow4" type="vtype6" route="B470" begin="60"  end="604800" period="604800"/&gt;
     &lt;flow id="flow5" type="vtype6" route="B470" begin="75"  end="604800" period="604800"/&gt;
     &lt;flow id="flow6" type="vtype6" route="B470" begin="90"  end="604800" period="604800"/&gt;
     &lt;flow id="flow7" type="vtype6" route="B470" begin="105"  end="604800" period="604800"/&gt;
     &lt;flow id="flow8" type="vtype6" route="B470" begin="120"  end="604800" period="604800"/&gt;
     &lt;flow id="flow9" type="vtype6" route="B470" begin="125"  end="604800" period="604800"/&gt;
     &lt;flow id="flow10" type="vtype6" route="B470" begin="130"  end="604800" period="604800"/&gt;
     &lt;flow id="flow11" type="vtype6" route="B470" begin="135"  end="604800" period="604800"/&gt;
     &lt;flow id="flow12" type="vtype6" route="B470" begin="140"  end="604800" period="604800"/&gt;
     &lt;flow id="flow13" type="vtype6" route="B470" begin="145"  end="899" period="15"/&gt;
     &lt;flow id="flow14" type="vtype6" route="B470" begin="900"  end="21599" period="3600"/&gt;
     &lt;flow id="flow15" type="vtype6" route="B470" begin="2700" end="21599" period="3600"/&gt;
  </code></pre>
  
  <p>In a normal case the vehicles shall appear in SUMO, according to the flows defined. The problem is that in my simulation vehicles appear spontaneously beginning with second <em>1014</em>.
  I get the id of vehicles with <code>nodeId = mobility-&gt;getExternalId();</code>. Normally id is looking like <code>flow13.4</code>. When not planned vehicles occur their id is looking like <code>vtype0_1</code>. So SUMO just chooses some <em>vType</em> from my definitions and starts it. In this way about 1000 new vehicles are added to my simulation. Why is this happening? Does anybody know, in what cases SUMO starts a vehicle, apart from defining a flow? 
  The occurrence of vehicles:</p>
  
  <pre><code>flow13.49 at 880
  flow14.0 at 900
  vtype4_0 at 1014
  vtype2_1 at 1027
  vtype4_2 at 1045
  </code></pre>