HP StorageWorks EVA Controller HSG V8.8 Software - Manual (Page 135)

Glossary
135 Command Console V2.5 User Guide
port
The hardware and software used to connect a host controller to
a communications bus, such as a SCSI bus or serial bus. On the
device side of the controller, a port is called a channel. The term
is sometimes also used to refer to the logical TCP/IP port that is
used to access the Agent over the network.
port/target/LUN (PTL)
For HS-series controllers, the complete address of a physical
disk on a device bus from which the controller derives the
device name. The name, “disk11300”, for instance, indicates a
physical device at port 1, target 13, and LUN 00.
RAID (Redundant Array
of Independent Disks)
RAID is an industry-standard set of techniques for configuring
an array of storage devices into host-accessible, virtual disks
with various cost, availability, and performance options.
Some common RAID levels are RAID 0, RAID 1, RAID 0+1,
RAID 3, RAID 3/5,and RAID 5.
RAID 0
RAID 0 is the industry-standard name for disk striping. A
RAID 0 virtual disk is also called a striped virtual disk.
In a RAID 0 virtual disk, host data is divided into strips spread
in a stripe across virtual disk member devices. This technique
provides much faster read and write performance than does
reading and writing to a single device. A three-device, RAID 0
virtual disk has potentially three times the bandwidth of a single
device because three separate small pieces of host data move in
parallel.
RAID 0 is the only RAID level that does not provide some level
of data redundancy. Because more devices can potentially fail
and because there is no way to recover data for a failed device,
RAID 0 virtual disks have less availability than
equivalent-sized single disks.