PlatinumNAS Owner’s Manual
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Read Through
Using this methodology, a read operation not only reads data from secondary
storage into system memory but also places the data into the cache such that future need for
the same data can be addressed expeditiously by directing a read operation for that data into
the cache only.
RAID Rebuild
When a RAID array enters into a degraded mode, it is advisable to rebuild the
array and return it to its original configuration (in terms of the number and state of working
disks) to ensure against operation in degraded mode
SATA
Acronym for “
Serial ATA
”. A hard disk drive interface standard developed to enhance
connectivity and speed over the IDE, or Parallel ATA disk interface. Current generation SATAII
supports speeds up to 300MB/S.
SCSI
This is an acronym for “
S
mall
C
omputer
S
ystem
I
nterface”. It is a high-speed parallel
communication scheme permitting data transfer rates of up to 320 MB/sec using the Ultra320
specification. The current specification supports up to 15 devices per channel with domain
validation and CRC error checking on all transferred data.
Secondary Storage
Mass storage devices such as hard disks, magneto-optical disks, floppy
disks and tapes are frequently referred to as secondary storage.
Secure Sockets Layer (SSL)
is a cryptographic protocol which provide secure communications
on the Internet. SSL provides endpoint authentication and communications privacy over the
Internet using cryptography. In typical use, only the server is authenticated (i.e. its identity is
ensured) while the client remains unauthenticated; mutual authentication requires public key
infrastructure (or PKI) deployment to clients. The protocols allow client/server applications to
communicate in a way designed to prevent eavesdropping, tampering, and message forgery.
Secure Webdisk uses SSL.
Also known as:
Transport Layer Security (TLS)
Server Message Block (SMB)
a network protocol mainly applied to share files, printers,
serial ports, and miscellaneous communications between nodes on a network. It also provides
an authenticated Inter-process communication mechanism. SMB and its successor, CIFS, are
the native network protocol used by the Microsoft Windows family, and is also used by Apple
MacOS X and is available for virtually every UNIX and Linux operating system.
Stripe
A stripe is a logical space that spans across multiple hard disks with each constituent
hard disk contributing equal strips (or chunks) of space to the stripe.
Stripe Set
A stripe set is a set of stripes that spans across multiple hard disks. In the figure
below, the displayed stripe set has 4 stripes, with strip number 1 comprised of the purple
strips 1A, 1B and 1C. Stripe number 2 is comprised of the green strips 2A, 2B and 2C etc.
Stripe Size
This is the size of the strips that constitute each stripe. This term is a misnomer
– though prevalent – since it should appropriately be called strip size or chunk size.
D-Glossary