PCTV Systems w-lantv 50n, Руководство пользователя

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PCTV Systems – w-lan tv 50n
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N
Netmask: A netmask is a mask used to divide an IP address into subnets and
specify the networks available hosts
R
Router: Routers, also known as "Intermediate Systems (IS)", are linking
elements that interconnect two or more subnetworks. In addition to acting as a
bridge, routers can expand the boundaries of a network (number of nodes,
physical extension). Routers also control data traffic by not forwarding defective
data packets.
S
Short GI: is a guard intervals used for transmitting data. The purpose of a guard
interval is to introduce immunity to propagation delays, echoes, and reflections
to which digital data is normally very sensitive.
Short means the length of the guard interval is 400ns.
SSID: is the abbreviation of “Service set identifier” and it is a name that
identifies a particular 802.11 wireless LAN. As the SSID displays to users, it
normally consists of human-readable ASCII characters.
Streaming:
The act of transferring compressed video and audio files over the
Internet. Streaming does not download all the data at once, but downloads it in
stages using a store-and-forward method. The data does not arrive as a
continuous file, but is cached in the buffer, which can create delays at the start
of transmission. The data can be transmitted live or it can be downloaded later.
The computer receiving the data stream must have a program (player) installed
on it to be able to decompress the data. Players are usually installed in browsers
such as Internet Explorer. The speed and quality of the data depend heavily on
how much bandwidth is available. In order to ensure smooth playback, the
Internet connection should offer at least 300 Kbps in bandwidth. There are
various file formats for audio and video streaming. The most popular formats
are MP3, RealAudio and WMA.
Subnet: A subnet or subnetwork comprises the components of a network that
have a partially-coinciding network address, but nevertheless a separate