Glossary of Storage-Related Terms & Acronyms
Cisco Small Business NSS2000 Series Administration Guide
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SAN (Storage Area Network): A network of storage and server devices typically
found in large, enterprise environments with high volume or high data traffic
requirements. SANs are architected to be scalable so that computer storage
devices (such as disk array controllers, tape libraries, and servers) can be added
and incorporated into the system. A SAN lets computers connect to hard disk
drives and tape drives on a network as though they were locally attached devices.
A SAN can contain a single NAS device or numerous NAS devices.
SAS (Serial Attached SCSI): A computer bus technology and serial
communication protocol to transfer data to and from hard disk drives and CD-
ROMs. Used in large enterprise environments to replace legacy, parallel, SCSI
solutions, because SAS attains much higher transfer speeds, and has backwards-
compatibility with SATA. SAS uses serial communication to establish connectivity
to other SAS devices and uses SCSI commands for file transfer.
SATA: Serial ATA. A computer bus technology that evolved from the Parallel ATA
physical storage interface. Like PATA, SATA is an IDE (Integrated Drive Electronics)
drive, designed for transfer of data to and from a hard disk. Serial ATA is a serial
link -- a single cable with a minimum of four wires creates a point-to-point
connection between devices. Transfer rates for Serial ATA begin at 150 MBps.
One of the main design advantages of Serial ATA is that the thinner serial cables
facilitate more efficient airflow inside a form factor and also allow for smaller
chassis designs. The IDE cables used in parallel ATA systems are bulkier than
Serial ATA cables and can only extend to 40cm long, while Serial ATA cables can
extend up to one meter.
SATA II: A followup set of specifications to the original SATA specifications. The
SATA II enhancements are delivered in increments. The first increment, called
SATA II: Extensions to SATA 1.0. was released in 2002 and focused on the
immediate needs for the server and network storage segments. Additional
increments of the specification will focus on enhanced cabling, fan-out and failover
capabilities and next generation signaling speeds. In spring 2003, two incremental
developments were announced: a SATA II Port Multiplier specification release
candidate and the completion and pending adoption of the SATA II Cables and
Connectors Volume 1 specification.
SFTP: Secure File Transfer Protocol. A network protocol designed by the IETF to
provide secure file transfer and manipulation facilities over the secure shell (SSH)
protocol. This protocol is NOT supported by the NSS. (It does support FTPS.)
