User guide
Glossary   
AMOL I and II  Automatic Measure of Line-ups I and II: Used by automated 
equipment to measure programme-viewing ratings. 
ARP  Address Resolution Protocol. A protocol used to "resolve" IP 
addresses into underlying Ethernet MAC addresses. 
ASI 
Asynchronous Serial Interface. 
ASIC  Application-Specific Integrated Circuit: A customized chip designed 
to perform a specific function. 
Async 
Asynchronous. 
ATM  Asynchronous Transfer Mode: A connection orientated, cell based, 
data transport technology designed for Broadband ISDN (B-ISDN). 
It provides a circuit-switched bandwidth-on-demand carrier system, 
with the flexibility of packet switching. It offers low end-to-end delays 
and (negotiable on call set up) Quality of Service guarantees. 
Asynchronous refers to the sporadic nature of the data being 
transmitted. Cells are transmitted only when data is to be sent, 
therefore the time interval between cells varies according to the 
availability of data. 
ATSC  Advanced Television Standards Committee: An organization 
founded in 1983 to research and develop a digital TV standard for 
the U.S.A. In late 1996, the FCC adopted the ATSC standard, the 
digital counterpart of the NTSC standard. 
B3ZS  Bipolar with Three Zero Substitution: A method of eliminating long 
zero strings in a transmission. It is used to ensure a sufficient 
number of transitions to maintain system synchronization when the 
user data stream contains an insufficient number of 1s to do so. 
B3ZS is the North American equivalent of the European HDB3. 
Backward 
Compatibility 
Refers to hardware or software that is compatible with earlier 
versions. 
BAT  Bouquet Association Table: Part of the service information data. The 
BAT provides information about bouquets. It gives the name of the 
bouquet and a list of associated services. 
baud rate  The rate of transfer of digital data when the data comprises 
information symbols that may consist of a number of possible states. 
Equivalent to bit rate when the symbols only have two states (1 and 
0). Measured in Baud. 
BER  Bit Error Rate: A measure of transmission quality. The rate at which 
errors occur in the transmission of data bits over a link. It is 
generally shown as a negative exponent, (e.g., 10-7 means that 1 in 
10,000,000 bits are in error). 
BISS  Basic Interoperable Scrambling System: Non-proprietary encryption 
from EBU (Tech3290). 
Bit rate  The rate of transfer of digital data when the data comprises two logic 
states, 1 and 0. Measured in bit/s. 
Block; Pixel Block  An 8-row by 8-column matrix of luminance sample values, or 64 
DCT coefficients (source, quantized, or de-quantized). 
  2/1553-FGC 101 1014 Uen B 
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