Cisco Cisco HDT Network Storage Hard Drive Trays Administrator's Guide

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Glossary of Storage-related Terms and Acronyms
Linksys Small Business NSS4000 and NSS6000 Series Network Storage System Administration Guide
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D
Striping: A method of concatenating multiple disk drives into one logical storage 
unit. Striping involves partitioning each drive’s storage space into stripes which 
may be as small as one sector (512 bytes) or as large as several megabytes. 
These stripes are then interleaved round-robin, so that the combined space is 
composed alternately of stripes from each drive. In effect, the storage space of 
the drives is shuffled like a deck of cards. The type of application environment, I/O 
or data intensive, determines whether large or small stripes should be used. 
T
Terabyte (TB): For data storage capacity usage, terabyte is equal to 1024 
gigabytes.
TFTP (Trivial File Transfer Protocol): A simple file transfer protocol used to transfer 
small files between hosts on a network. TFTP works like a very basic form of FTP.
TLS: Transport Layer Security. A security protocol from the IETF that is based on 
the Secure Sockets Layer (SSL) 3.0 protocol developed by Netscape. TLS uses 
digital certificates to authenticate the user and the network. The TLS client uses 
the public key from the server to encrypt a random number and send it back to the 
server. The random number, combined with additional random numbers previously 
sent to each other, is used to generate a secret session key to encrypt the 
subsequent message exchange. 
U
UPnP: Universal Plug and Play. A family of protocols from the UPnP Forum that 
automatically configure devices, discovering services and providing peer-to-peer 
data transfer over an IP network. Like Zeroconf, UPnP uses link-local addressing 
for IP assignment and provides service discovery. Unlike Zeroconf, UPnP uses a 
different protocol. If a device does not have an IP address and there is no DHCP 
server in the network, UPnP employs link-local addressing to create an IP address. 
Software such as Windows Media Connect uses UPnP to stream audio and video 
over the network. Several UPnP standards are employed including the Simple 
Service Discovery Protocol (SSDP) for finding devices and UPnP AV Architecture, 
MediaServer and MediaRenderer for streaming. UPnP can open router ports to let 
a device, external to the network, contact a network device. 
UPS: Uninterruptible Power Supply. A device that provides battery backup when 
the electrical power fails or drops to an unacceptable voltage level. Small UPS 
systems provide power for a few minutes; enough to power down the computer in 
an orderly manner, while larger systems have enough battery for several hours.