Ericsson AVP 1000 Reference Manual page 404

Glossary
GOP
GUI
HDTV
HPA
HSYNC
HTTP
HU
Hub
ICAM
ICMP
IGMP
IDU
IEC
IF
Interframe Coding
A-8
Group of Pictures: MPEG video compression works more effectively
by processing a number of video frames as a block. The Ericsson
AB Encoder normally uses a 12 frame GOP; every twelfth frame is
an I frame.
Graphical User Interface: The use of pictures rather than just words
to represent the input and output of a program. A program with a
GUI runs under a windowing system and has a screen interface
capable of displaying graphics in the form of icons, drop-down
menus and a movable pointer. The on-screen information is usually
controlled / manipulated by a mouse or keyboard.
High Definition Television.
High Power Amplifier: Used in the signal path to amplify the
modulated and up-converted broadcast signal for feeding to the
uplink antenna.
Horizontal (line) SYNCs.
HyperText Transfer Protocol. The fundamental protocol used on the
Internet for transmission of WEB pages and other data between
servers and PCs
Height Unit
A device in a multi-point network at which branch nodes
interconnect.
Integrated Conditional Access Module: Embedded in the IRD and
responsible for descrambling, plus packet filtering and reception. It
also contains the physical interface to the subscriber's viewing card.
Internet Control Message Protocol. ICMP messages, delivered in IP
packets, are used for out-of-band messages related to network
operation or mis-operation
Internet Group Management Protocol. IGMP is a protocol used to
manage multicasts on the Internet. For a host (receiver unit) to
receive a multicast, it needs to transmit IGMP "join" messages on
the right format. Three versions exist. IGMPv2 is common today but
IGMPv3 is the next step.
Indoor unit
International Electrotechnical Committee.
Intermediate Frequency: Usually refers to the 70 MHz or 140 MHz
output of the Modulator in cable, satellite and terrestrial transmission
applications.
Compression coding involving consecutive frames. When
consecutive frames are compared, temporal redundancy is used to
remove common elements (information) and arrive at difference
information. MPEG-2 uses B and P frames, but since they are
individually incomplete and relate to other adjacent frames, they
cannot be edited independently.
EN/LZT 790 0023/1 R16A