Compaq 4200 User Manual page 78

Glossary–2 Compaq StorageWorks Enclosure 4200 Family LVD Disk Enclosures User Guide
carrier
CE-Mark
compatible device
controller
controller enclosure
CRU
customer replaceable
unit
device ID
differential SCSI bus
disk
disk array controller
disk enclosure
The container in which storage devices are mounted to form CRUs.
Carriers are available in 3.5-inch form-factors for both low-profile
(1.0-in) and half-height (1.6-in) disks.
A European Economic Community (EEC) certification label that
identifies electronic devices authorized for sale within member nations.
A storage device that has been tested in a specific enclosure and found to
be compatible
1. A hardware–firmware device which manages communications on
behalf of host systems over the SCSI bus to devices. Controllers typically
differ by the type of interface to the host and provide functions beyond
those the devices support. 2. A stand-alone device which connects a host
adapter to the storage SCSI bus. This device provides RAID functionality,
typically has multiple SCSI bus ports, performs the lower layers of the
SCSI protocol, and normally operates in the initiator role.
See also array controller.
A StorageWorks enclosure containing a controllers, cache modules,
power supplies, and blowers with either I/O modules or SCSI bus
connectors.
Customer replaceable unit. An enclosure element that the customer can
replace without using special tools or techniques.
See CRU.
See SCSI ID.
A bus in which the signal level is determined by the potential difference
between two wires. A differential bus is more robust and less subject to
electrical noise than is a single-ended bus.
Differential buses may be either low voltage (LVD) or high voltage
(HVD).
A storage device supporting random access to fixed size blocks of data
See controller.
A Compaq enclosure dedicated to supporting disk drives. Such an
enclosure includes the power supplies, blowers, I/O modules, and an
EMU.