text: Figure 3-1 IP addressing scheme: Use of a single subnet 
  
  **3.5.1 Firewall planning**
  
  After you have your IP network planned, identify network flows that are required for the 
  correct functioning of the environment. The list must specify source IP address, destination IP 
  addresses, and required protocols or ports for each flow. Present the list to the firewall 
  administrators and request the set up of appropriate firewall rules. 
  
  For a list of mandatory and optional network flows that are required for operating IBM SAN 
  Volume Controller, search for “TCP/IP requirements for the system” at IBM Knowledge 
  Center. 