Dell PowerEdge RAID Controller H700 - Manual (Page 167)

Glossary 167
Patrol Read
A preventive measure that includes review of your system for possible physical
disk errors that could lead to disk failure and damage data integrity.
Passphrase
The user supplied string that the controller uses to create the security key
PHY
The interface required to transmit and receive data packets transferred across
the serial bus.
Each PHY can form one side of the physical link in a connection with a PHY on
a different SATA device.
Physical Disk
A non-volatile, randomly addressable device for storing data. Physical disks are
rewritable and can also referred to as hard drives and solid state drives (SSDs).
Protocol
A set of formal rules describing how to transmit data, generally across a network
or when communicating with storage subsystems. Low-level protocols define
the electrical and physical standards to be observed, bit- and byte-ordering, and
the transmission and error detection and correction of the bit stream. High-level
protocols deal with the data formatting, including the message syntax, the
terminal to system dialogue, character sets, sequencing of messages, etc.
R
RAID
Redundant Array of Independent Disks (originally Redundant Array of
Inexpensive Disks). It is an array of multiple independent physical disks
managed together to yield higher reliability and/or performance exceeding that
of a single physical disk. The virtual disk appears to the operating system as a
single storage unit. I/O is expedited because several disks can be accessed
simultaneously. Redundant RAID levels (RAID levels 1, 5, 6, 10, 50, and 60)
provide data protection.
PERC7.2_UG.book Page 167 Thursday, March 3, 2011 2:14 PM