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Arbitrated loop, also known as FC-AL, is a Fibre Channel topology that requires no fibre channel switches. Devices are connected in a one-way loop fashion in a ring topology. Image File history File links Broom_icon. ... Image File history File links Simple diagram of Arbitrated Loop in a Private Loop Mode. ... Image File history File links Simple diagram of Arbitrated Loop using a Hub in a Public Loop Mode connected to a switch via FL_port. ... This article or section does not adequately cite its references or sources. ... This article or section does not adequately cite its references or sources. ... Image showing ring network layout A ring network is a network topology in which each node connects to exactly two other nodes, forming a circular pathway for signals: a ring. ...

• It is a serial data architecture that is compatible with SCSI, handling up to 126 devices per port (NL port). It handles 127 devices if counting the 1 port connected to an optional fabric switch port. Only one connection may be a switch port.
• The bandwidth on the loop is shared among devices.
• Only 2 devices on the loop are communicating at any one time.
• Naturally if only 2 devices are left in the loop, the topology becomes Point-to-Point.
• Arbitrated Loop can be connected in a daisy chained fashion or a hub fashion. The daisy chain fashion will raise problems if one of the devices in the chain failed. The hub fashion will allow the loop to continue in case any device on the loop failed. An enhanced low-cost solution is also using a loop switch (as opposed to a fabric switch). Loop switches provide considerable performance improvements over hubs without much additional cost.
• Arbitrated Loop uses NL_port, FL port.
• An Arbitrated Loop with a fabric port, FL_Port, is considered a public loop.
• An Arbitrated Loop with no fabric port, FL_Port, is considered a private loop.
• NL_Port must provide Logon and Name registration facilities to login into the Fabric.
• F/NL Port - For use with a non-Fabric switched Loop topology, Provides loop logon services, Provides name registration services.

It has been suggested that this article be split into multiple articles accessible from a disambiguation page. ... This article or section does not cite any references or sources. ... The following lists varios types of Fibre Channel ports: E_Port: expansion port F_Port: Fabric port, not loop capable FL_Port: Fabric port, not loop capable G_Port: generic port, can operate as a E_port or F_port ... Point-To-Point is a Fibre Channel topology where two devices are directly connected to each other. ... The following lists varios types of Fibre Channel ports: E_Port: expansion port F_Port: Fabric port, not loop capable FL_Port: Fabric port, not loop capable G_Port: generic port, can operate as a E_port or F_port ...

See also

• Storage area network
• Fibre Channel
• Switched fabric
• List of Fibre Channel standards