This is the World Wide Name identifying this FCIP device's fabric, with a zero-length value specifically meaning the WWN has not been assigned or is currently unknown. Because WWNs are how Fibre Channel fabrics uniquely identify and authenticate peer entities, an unassigned value here would prevent this device from being properly recognized when establishing FCIP links to peer entities that check for a specific remote WWN. A newly installed MDS switch showing a zero-length value for this object before its fabric identity has been provisioned would need that WWN assigned before other FCIP links configured to expect a specific remote WWN could connect to it.