ssion manager interface, 
  <code>org.apache.catalina.Manager</code>
  A cluster manager must implement the <code>org.apache.catalina.ha.ClusterManager</code> and is solely 
  responsible for how the session is replicated.<br>
  There are currently two different managers, the <code>org.apache.catalina.ha.session.DeltaManager</code> replicates deltas 
  of session data to all members in the cluster. This implementation is proven and works very well, but has a limitation
  as it requires the cluster members t