Glossary

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.

Manual No. 775051

G-21