Glossary
SuperLoader 3 Autoloader User’s Guide
185
self cleaning head
Found in all DLT tape drives. Tiny ridges on either
side of the DLT drive read/write head continuously wipe the
tape clean as it passes over the head. This is why there is no
periodic cleaning prescribed for DLT tape drives.
server
A powerful computer system with a large hard disk drive that
serves the information access and communication needs of
multiple users. Often servers are dedicated to a particular
function such as Internet access, printing, file management,
backup, and network communications.
servo data
Magnetic markings written on the media that guide the read/
write heads to the proper position.
shelf life
The length of time that a tape can be stored without losing its
magnetic strength. For DLTtape media, this period is 30 years or
more.
shock rating
A rating, expressed in Gs which stands for multiples of
gravity, of how much shock a tape drive can sustain without
damage. Operating and non-operating shock levels are usually
specified separately.
SMTP
Simple Mail Transfer Protocol. An e-mail protocol on the Internet
that defines the message format and the message transfer agent.
SNMP
simple Network Management Protocol. A protocol that monitors
and controls a network.
SNTP
Simple Network Time Protocol. SNTP is based on NTP, the
Network Time Protocol, an industry standard way for computers
to synchronize their time to an external reference standard. NTP
and SNTP are fully interoperable. Each consists of a client, for
example the SuperLoader, which obtains the current time (in
UTC) from either an SNTP server or an NTP one. SNTP and NTP
are in wide use on the Internet. NTP is specified by RFC1305.
SNTP is specified by RFC2030.
soft error
A faulty data reading that does not recur if the same data is
reread from the disk or corrected by ECC. Usually caused by
power fluctuations or noise spikes.
stacker
A tape automation system that sequentially loads and unloads
tape cartridges. does not provide random access to cartridges of
the data stored on them.
stepper
A type of motor that moves in discrete amounts with each
electrical pulse.
