ND SatCom SKYWAN IDU 7000, Manual

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2010-10-26 Network Design and Engineering Guide 143
Appendix C - Glossary
Intermediate Frequency
(IF) From radio frequency (RF) down converted signal frequency
used on the link between IDU and ODU. In a
Sky WAN
®
net-
work L-Band is used as intermediate frequency.
Interface Set of definitions to describe the communication boundary be-
tween two systems or entities (seen as black boxes). Used in
an overall context if you speak about logical (software) and
physical (hardware) definition. See also Port.
Ka Band Frequency band with uplink 26.5 to 40GHz; downlink 18 to 20
GHZ, this band is primarily used for two way consumer broad-
band. The higher frequencies of Ka band are significantly more
vulnerable to signal quality problems caused by rain fade. See
also Rain Fade.
Ku Band Frequency band with uplink 13.75 - 14.5 GHz; downlink 10.9
to 12.75 GHz. Typically allows more powerful transmission
from the satellite but is also more susceptible to rain fade than
C Band. See also Rain Fade.
Latency Latency in a packet switched network is an accumulation of de-
lays caused by network devices and transmission process. A
combination of propagation, queuing and processing delays is
usually named network latency profile. See also Propagation
Delay and Processing Delay.
Low Noise Block Down
Converter (LNB) Combination of Low Noise Amplifier and down converter built
into one device attached to the feed. It is used for the downlink
satellite transmission by converting a band from a higher fre-
quency to a lower frequency.
L Band Frequency band from 1 to 2 GHz, in a Sky WAN
®
network this
band is the result of the down conversion of the received down-
link satellite signal from the LNB.
Master Station in a Sky WAN
®
network that will grant network access
and bandwidth to slave stations. The master generates a
frame plan containing capacity assignment according to re-
quests collected from all stations and sends it back to them via
the reference burst. See also “Slave”.
Mesh network Topology whereby a remote VSAT location communicates
with another remote location without routing through a hub.
Microflow Sequence of IP packets that will have source- and destination
IP addresses and TCP/UDP port numbers in common.
MF TDMA Multiple Frequency Time Division Multiple Access (MF TDMA)
is a broadband access method where different data streams
are put into different slots that are separated by both, frequen-
cy and time.
Term Definition