Click here for more SAN School lessons. A WWN is a 64-bit address that is used within the Fibre Channel spec for assigning a unique ID to each element within a Fibre Channel fabric and is handed out to vendors from the IEEE. The format is as follows:
A worldwide unique identifier for the node.
A worldwide unique identifier for each N_PORT associated with the node.
For each N_PORT attached to a fabric, a 24-bit fabric-unique address.
The fabric address is the address to which frames are sent. The fabric address is as follows: The 24-bit FC address is not really part of the world-wide name. It is only used for routing data within the SAN.
This was first published in April 2004