What is WWNN and WWPN ?

A WWPN (World Wide Port Name) is physically assigned to a part in a Fibre Channel device.

The WWNN (World Wide Node Name) is a World Wide Name assigned to a node in a Fibre Channel fabric. It is valid for the same WWNN to be seen on many different ports on the netwerk.

The WWNN can be regenerated not like the WWPN which can't.

   A WWNN (World Wide Node Name) is physically connected to a Fibre Channel device such as a FC HBA or storage array. It is valid for the same WWNN to be seen on many different ports (different addresses) on the network, identifying the ports as multiple network interfaces of a single network node.

   The WWPN (World Wide Port Name) is generated from the WWNN by the Fibre Channel fabric when the device logs into the fabric. Used on storage area networks, it performs a function equivalent to the MAC address in Ethernet protocol, as it is supposed to be a unique identifier in the network.

WWNN stands for World Wide Node Name - which is a single pool is created for all the blades in the system. As this pool is for the parent FC device node (the card itself), it is not necessary to create one for each fabric.

WWPN stands for World Wide Port Name which is a pool created for all the blades in the system. The WWPNs are assigned to the ports when the vHBA templates are created

this is addressing on  FC fabrics and it is similar to MAC address 

WWNN: World Wide Node Name ( device or HBA Address )

for example :::::b4:eg:b3:4b

WWPN: World Wide Port Name : address for specific port

 note: 

A dual-port HBA would have a single WWNN and Two WWPNs  

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