Annex A

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

A process (in digital transmission) used to combine a digital signal

Scrambling

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.

A-16

EN/LZT 790 0005 R1A