title: MPI:Ring topology:why nodes can connect even they are not neighbors?
body: <p>Ring topology definitions:<br>
  We will assume that the nodes of a ring are connected so that node
  i has neighbors i − 1 (left) and i + 1 (right), 1 ≤ i &lt; p − 1. Nodes 0 and p − 1 are still neighbors .<br>
  When using with flat tree algorithm for broadcast,root node must send messages to all other processes . <br>
  Why can root node connect with all of other processes when it has only two neighbors (left and right) ??</p>