HP StorageWorks 2/140 director product manager user guide - Page 210

Glossary arbitration Process of choosing one device from a collection of devices that request service simultaneously. audit log Log summarizing actions (audit trail) made by the user. authentication Verification of identity for a person or process. backplane The backplane provides 48 VDC power distribution and connections for all logic cards. backup FRU When an active FRU fails, an identical backup FRU takes over operation automatically (failover) to maintain director and Fibre Channel link operation. Contrast with active FRU. BB_Credit See buffer-to-buffer credit. beaconing Use of light-emitting diodes on ports, port cards, field-replaceable units, and directors to aid in the fault-isolation process; when enabled, active beaconing causes LEDs to flash for selected components. BER See bit error rate. bidirectional In Fibre Channel, the capability to simultaneously communicate at maximum speeds (100 Mbps) in both directions over a link. bit error rate (BER) Ratio of received bits that contain errors to total of all bits transmitted. blocked port Devices communicating with the port are prevented from logging into the director or communicating with other devices attached to the director. A blocked port continuously transmits the offline sequence. Glossary-2 director product manager user guide