• Ports are intelligent interface points in a Fibre Channel SAN: – Embedded in an HBA – Embedded in an array or tape controller – Embedded in a fabric switch
• Ports communicate with other ports Ports
HBA Server Tape device Switch
Subsystem controller
Storage
Ports connect devices to the Fibre Channel network: Ports transmit and receive data to and from the network. Ports are found in nodes, switches and bridges/routers. Node ports are the interface between FC and the device’s internal bus architecture (e.g. PCI bus in hosts, SCSI bus in some subsystems).
Depending on where the port is located, and what it is connected to, it may have a different logical behaviour, so there are different logical port types. Each port has a unique World Wide Port Name (WWPN), a unique identifier. Each port will also be associated with a FC_ID (Fibre Channel ID) – a 24 bit address.
The WWPN follows the device. For example, if the device is moved from a port on one switch to a port on another switch (even if it is in the same fabric) the WWPN will remain the same (it identifies the device) but the FC_ID will change.
The FC_ID is used for switching and routing purposes. All logical ports are associated with World Wide Port Names and they will get an FC_ID.