title: PipeLine Processing Engine
body: <pre><code>P1----&gt;P2-----&gt;(output 1)
  P1----&gt;P3----&gt;(output 2)
  (output 1) + (output 2) ----&gt;P4
  </code></pre>
  
  <p>P1 Process execute, P1 output is entered in P2 process as a input. P2 will also execute. P4 should start only when P2 &amp; P3 complete process. P4 Process will not started since input process P3 is not yet processed (P2 input is available now). </p>
  
  <p>Any input parameter trigger mechanism which will trigger P4 execute process.
  I need any standard design pattern or sample code (C#) which will solve above problem.</p>
  
  <p>Also need any standard way by which we can execute process parallel in .net 3.5 framework.</p>