Network Technologies ASI-IP-GTW User Manual

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ASI-IP-GTW User's Manual 
 
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7  Appendix A: Glossary 
1000Base-T: The term for the Electrical Gigabit Ethernet interface. This 
is the most common interface for Gigabit Ethernet. Most Gigabit-
enabled PCs and equipment use this interface. 
ARP: Address Resolution Protocol. A protocol used to "resolve" IP 
addresses into underlying Ethernet MAC addresses.  
ATSC: Advanced Television Systems Committee. An American 
organisation working with standardisation of digital television 
broadcasts, primarily in the US but also in Asia and other parts of the 
world.  
DiffServ: Differentiated Services. A mechanism used on layer 3 - e.g. 
the IP layer - to differentiate between traffic of various types. DiffServ is 
based on the ToS field and provides a mechanism for the network to 
give e.g. video traffic higher priority than other traffic (for example 
Internet traffic). 
DVB: Digital Video Broadcasting. The European consortium defining 
standards for transmission of digital TV broadcasts, primarily in 
Europe.  
DVB ASI: Digital Video Broadcasting Asynchronous Serial Interface. A 
common physical interface for transmission of MPEG2 Transport 
Streams (i.e. MPEG2-compressed video) over a serial interface, typically 
coaxial cables. 
DWDM: Dense Wavelength Division Multiplexing. A mechanism to 
utilize existing fiber with even more bandwidth by adding extra signals 
using other wavelengths/colors. 
Ethernet: Originally a 10Mbit/s shared medium network type 
developed by Xerox. Later transformed into an official standard. 
Nowadays, most Ethernet networks are based on full duplex 
connections over twisted pair cables. Ethernet switches in the network 
take care of routing Ethernet frames between nodes. The speeds now 
supported are 10Mbit/s, 100Mbit/s and 1000Mbit/s. 10Gigabit/s 
Ethernet networks are now emerging. 
FEC: Forward Error Correction. A mechanism to add extra data to a 
transmission in order to protect it. Dependent on the amount of extra 
data added, the receiver will be able to correct errors (i.e. regenerate 
lost packets) in case of network packet loss. 
HDTV: High Definition Television. The new, coming television 
standard(s) that gives clearer and more detailed TV pictures. Many TV 
sets sold today (especially flat-screen TVs) are prepared for high 
definition TV. 
HTTP: HyperText Transfer Protocol. The fundamental protocol used on 
the Internet for transmission of WEB pages and other data between 
servers and PCs. 
ICMP: Internet Control Message Protocol. ICMP messages, delivered in 
IP packets, are used for out-of-band messages related to network 
operation or mis-operation. 
IGMP: 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