Ericsson MX8400, Справочное руководство

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Glossary
ROM Read Only Memory: A non-volatile storage device for digital data.
Data has been stored permanently in this device. No further
information may be stored (written) there and the data it holds
cannot be erased. Data may be read as often as required.
RS Reed-Solomon coding: An error detection and correction, coding
system. 16 bytes of Reed-Solomon Forward Error Correction code
are appended to the packet before transmission bringing the packet
length to 204 bytes. The 16 bytes are used at the receiving end to
correct any errors. Up to eight corrupted bytes can be corrected.
RSVP ReSerVation Protocol. A Quality-of-service oriented protocol used
by network elements to reserve capacity in an IP network before a
transmission takes place.
RTP Real-time Transfer Protocol. A protocol designed for transmission of
real-time data like video and audio over IP networks. RTP is used
for most video over IP transmissions.
RLC Run Length Coding: Minimization of the length of a bit-stream by
replacing repeated characters with an instruction of the form ‘repeat
character x y times’.
SCPC Single Channel Per Carrier.
Spectral
Scrambling A process (in digital transmission) used to combine a digital signal
with a pseudo-random sequence, producing a randomized digital
signal that conveys the original information in a form optimized for a
broadcast channel.
Scrambling Alteration of the characteristics of a television signal in order to
prevent unauthorized reception of the information in clear form.
SDI Serial Digital Interface.
SDT Service Description Table: Provides information in the SI stream
about the services in the system; for example, the name of the
service, the service provider, etc.
SDTI Serial Data Transport Interface. A mechanism that allows
transmission of various types of data over an SDI signal. This may
be one or more compressed video signals or other proprietary data
types. The advantage of SDTI is that existing SDI transmission
infrastructure can be used to transport other types of data.
SELV Safety Extra Low Voltage (EN 60950).
SFP Small Form-factor Pluggable module. A standardized mechanism to
allow usage of various optical interfaces for Gigabit Ethernet.
Several types of SFP modules exist: Single-mode fiber modules for
long-distance transmission and multi-mode fiber modules for shorter
distances. SFP is also known as "mini-GBIC".
SIP Session Initiation Protocol. A common acronym for the ongoing
effort to standardize signaling over IP networks, i.e. connection
set-up and tear-down. SIP makes it possible to "dial" a remote
receiver of data and set-up the connection in this way.
2/1553-FGC 101 1014 Uen B A-16