8.2. Fibre Channel Terminology

To fully understand the methods employed by Fibre Channel technology, a solid comprehension of the most common Fibre Channel terms is essential. Following are the key terms with which you need to be familiar:

• Node Fibre Channel devices are called nodes. A node can be a computer (host), adapter, or any device containing one or more Fibre Channel ports.

• Node ID The node ID is a unique identifier for a node.

• Port Each node must have at least one port to provide access to other devices if it is connected to a Fibre Channel topology. The port on the node is known as an N_port. In the port-naming convention, N designates node, L designates loop, and F designates fabric. The Fibre Channel port names, types, topologies, and descriptions are listed in the following table.

  Port	Type	Topology	Description
  N_port	Node	Point to point or fabric	The port on a specific node
  NL_port	Node	Arbitrated loop	The node connected to an arbitrated loop
  F_port	Fabric	Switched fabric	The fabric port
  FL_port	Fabric	Switched fabric	The fabric connected to an arbitrated loop
  L_port	Loop	Arbitrated loop	The hub port on an arbitrated loop

  
  

• Link Each Fibre Channel port uses a pair of optical fibers. One of the fibers carries information into the receiver port; the other fiber carries information out of the transmitter port. This pair of fibers is called a link.

• Topology A Fibre Channel topology is an interconnection scheme that connects two or more Fibre Channel N_ports. The three Fibre Channel topologies are point to point, FC-AL, and FC-SW.

Note

For more information on Fibre Channel technology, review A. F. Benner's book Fibre Channel: Gigabit Communication and I/O for Computer Networks.