beautypg.com

Acer PCI to Ultra SCSI RAID Controllers DAC960PG User Manual

Page 79

background image

Glossary

Manual No. 775012

G-21

drive 1, block 2 on SCSI drive 2, block 3 on SCSI drive 3, block 4 on SCSI
drive 1, block 5 on SCSI drive 2, and so on. This storage method increases
the disk system throughput by ensuring a balanced load among all drives.

Sustained Data Transfer Rate

A rate of data transfer defined for continuous operation at a maximum speed
level.

Synchronous Data Transfer

Data transmission synchronized to a defined time interval, and is faster than
asynchronous SCSI because there is no wait for acknowledgement of each
byte from the receiving device (up to 20MHz).

System Drives

A system drive is equivalent to a logical drive. System drives are presented
to the operating system as available disk drives, each with a capacity
specified by the eXtremeRAID controller.

Target ID

The SCSI ID of a device attached to a controller. Each SCSI channel can
have up to 15 attached SCSI devices (target ID from 0 to 6 and 8 to 15).

Terminator

A part used to end a SCSI bus.

Termination

A method of matching transmission impedance of a bus to eliminate signal
reflections from the physical ends of the bus.

Transfer Rate

The rate at which data moves between the host computer and storage, input,
or output devices, usually expressed as a number of characters per second.

Ultra 160 SCSI (Ultra3 SCSI)

The newest in SCSI technology, Ultra 160 SCSI increases performance,
reliability, and manageability. With transfer rates of 160 MBps, cyclical
redundancy check, and the capability to automatically test the interface’s
performance level, the Ultra 160 SCSI can keep up with fibre channel
technology.