Filter
Top Products
i
ATTO Technology Inc.
Glossary
The following terms are only a few examples of the language used for Fibre Channel, SCSI and storage systems.
For more information, visit the websites of these professional organizations: the Fibre Channel Industry
Association (www.fibrechannel.com); the Fibre Channel Consortium (www.iol.unh.edu/consortiums/index.html
click on Fibre Channel); the Storage Area Networking Industry Association (www.snia.org), or SCSI Trade
Association (www.scsita.org)
Fibre Channel technology
Fibre Channel is a serial communication interface
designed to transfer large amounts of data among a
variety of hardware systems over long distances. It is
becoming a key technology for applications that
require shared, high-bandwidth access to storage.
Fibre Channel provides a logical point-to point serial
channel for the transfer of data between a buffer at a
source device and a buffer at a destination device. It
moves buffer contents from one port to another,
without regard to the format or meaning of the data,
allowing different upper level protocols to run over the
Fibre Channel connection.
The Fibre Channel architecture is a hierarchical set of
protocol layers. Defined within these layers are rules
for signal interfaces, serial encoding and decoding,
error control, frame format and communications
protocols. Fibre Channel provides a range of
implementation possibilities and purposely isolates
the transmission medium from the control protocol so
that each implementation may use the technology best
suited to the application.
Fibre Channel arbitrated loop (FC-AL) technology
allows 127 systems and devices to be distributed over
a range of up to 10 kilometers running at speeds of 1
gigabit/sec. Multiple FC-AL loops can be connected
via a fabric switch topology to extend the range.
SAN technology
A Storage Area Network (SAN) is a shared storage
architecture. SANs connect computers and storage
devices for online data access. Each connected system
can directly access any attached storage device. A
SAN maintains greater fault tolerance and load
balancing by supporting server clustering and fail-over
(the ability for one server to take over for another in
the event of a failure.
SCSI protocol
SCSI (pronounced scuzzy) stands for Small Computer
System Interface, a processor-independent standard
for system-level interface between a computer and
SCSI devices such as hard disks, CD-ROM and
printers, and to other computers and local area
networks.
The protocol has many standards specifying data
transfer rates, data width and speeds which allow SCSI
devices to exchange data and control signals with a
computer's CPU. Each device connected to a SCSI bus
must have a different SCSI ID.
Term Definition
arbitrate process of selecting one L_Port from a collection of ports which ask for use of the
arbitrated loop at the same time
arbitrated loop a loop topology in which two or more ports are interconnected, but only two ports
can communicate at one time
ATA Advanced Technology Attachment: A disk drive interface standard, formerly called
IDE; the ATA specification deals with the power and data signal interface of an
integrated disk controller and drive
auto negotiation hardware senses and automatically responds depending on configuration
CLI Command Line Interface: used by applications and advanced users to perform
diagnostic or configuration tasks; access is available through a computer terminal
or terminal emulator via connections to the RS-232 port or the optional Ethernet
management services card via the local area network using Telnet
fabric A Fibre Channel switch or two or more Fibre Channel switches interconnected to
physically transmit data between any two N_Ports on a switch or switches