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What is WWN in fibre channel ?

WWN stands for World Wide Name in Fibre Channel (FC). It is a unique identifier assigned to each Fibre Channel device in a Storage Area Network (SAN). The WWN serves as a globally unique identifier for a device and is used to identify and address Fibre Channel devices within the SAN environment.

There are two types of WWNs used in Fibre Channel:


World Wide Port Name (WWPN): 

  • A WWPN is assigned to each Fibre Channel port on a device, such as a host bus adapter (HBA) or a Fibre Channel switch port.
  • The WWPN is a 64-bit value that is typically represented as a 16-digit hexadecimal number.
  • WWPNs are used to uniquely identify and address individual Fibre Channel ports within the SAN.
  • Devices with multiple Fibre Channel ports will have multiple WWPNs, one for each port.


World Wide Node Name (WWNN): 

  • A WWNN is assigned to each Fibre Channel device, such as a storage array or a host computer.
  • The WWNN is a 64-bit value, also represented as a 16-digit hexadecimal number.
  • WWNNs are used to uniquely identify and address the Fibre Channel device itself within the SAN.
  • Each Fibre Channel device will have a unique WWNN.

Together, the combination of WWPN (port-specific) and WWNN (device-specific) provides a unique identification for each Fibre Channel port and device within the SAN. This enables proper addressing and routing of Fibre Channel frames within the SAN fabric, allowing devices to communicate with each other.

WWNs are important in Fibre Channel SAN environments for zoning, configuration, management, and addressing purposes. They help ensure that the SAN operates efficiently and devices can be properly identified and controlled within the network.

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