HP StorageWorks 2000 Series Reference Manual page 257

Each controller has a unique, permanent hardware address. Each controller host port
has a unique, user-defined IP address.
The following table shows example hardware addresses and port IP addresses.
Both controllers have the same unique, permanent node WWN. Each controller host
port has a unique port WWN that is based on the node WWN. The WWN format is:
5 00
– The manufacturer's unique identifier, 00C0FF.
– A serial number derived from the last six hex digits of the
midplane serial number.
– 0 for controller A port 0; 1 for A1; 2 for B0; 3 for B1.
The following table shows example node WWNs and port WWNs. Notice that the
node WWNs are the same and the port WWNs differ in the fourteenth digit.