g-6 EMC Connectrix DS-32B2 and ED-12000B Fabric OS Reference Manual
Glossary
D
Data Word Type of transmission word that occurs within frames. The frame
header, data field, and CRC all consist of data words. See also Frame,
Ordered Set, and Transmission Word.
DB-9 Connector A 9-pin version of the RS-232C port interface. May be either the male
or female interface. See also RS-232 Port.
dBm, dBW Logarithmic units of power used in electronics. Indicates signal
strength in decibels above the reference level, which is 1 milliwatt for
dBm, and 1 watt for dBW. An increase of 10 dBm or 10 dBW
represents a 10-fold increase in power.
DCE Port A data communications equipment port capable of interfacing
between a DTE (data terminal equipment) port and a transmission
circuit. DTE devices with an RS-232 (or EIA-232) port interface
transmit on pin 3, and receive on pin 2. See also DTE Port and RS-232
Port.
Defined Zone
Configuration The set of all zone objects defined in the fabric. May include multiple
zone configurations. See also Zone Configuration.
Device A disk, a RAID, or an HBA.
Device Connection
Controls Enables organizations to bind an individual device port to a set of one
or more switch ports. Device ports are specified by a WWN and
typically represent HBAs (servers). See also Access Control List.
Disparity The relationship of ones and zeros in an encoded character. Neutral
disparity means an equal number of each, positive disparity m eans a
majority of ones, and negative disparity means a majority of zeros.
DLS Dynamic load sharing. Dynamic distribution of traffic over available
paths. Allows for recomputing of routes when an Fx_Port or E_Port
changes status.
Domain ID As applies to Departmental Switches, a unique number between 1
and 239 that identifies the switch to the fabric and is used in routing
frames. Usually automatically assigned by the switch, but can be
manually assigned.