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IP Based Multicast Streaming over Satellite : Concept
- Multimedia Satellite System Configuration
- Global Standard : DVB/MPEG2
- Client and Server Applications for Streaming
- Scrambling of Streams - Scheduler
- Case Study : SpeedCast Satellite ISP
Satellite
can be the optimum carrier for IP based multicast stream.
Multicast streaming service was basically designed to serve
point to multi-point receiver site, but standard Internet
protocol is designed mainly to support point to point communication
protocol.
IP
Stream can be generated from stream server applications such
as Netshow Server. The IP-DVB Gateway has a function to transform
this IP packet into standard DVB/MPEG2 stream. Multiplexer
combine this standard DVB/MPEG2 stream with any other standard
video or audio stream and transfer to satellite uplink facility.
Streams
can be originated from Netshow Servers, Real Audio and Video
Servers, Silicon Graphics Streaming Tools etc. The only requirement
is that the streaming tools use the IP protocol for the transport
of their data.
Streams
can be sent out in Free to Air (FTA) Mode or in scrambled
mode. In FTA mode streams are receivable on any DVB compliant
receiver card. In scrambled mode the broadcast can be specifically
addressed to those receivers with certain access rights. Scrambling
of streams can be done at two different lays; 1) IP Packet
Layer, 2) DVB Layer. The software scrambling system on IP
packet layer have more precise control over the multimedia
data delivery and it can also be highly flexible and easy
to implement to many standard receivers in the market.
DVB
scrambling mechanisms were originally designed with TV broadcasting
in mind can be used for the scrambling of multimedia streams.
They are however not flexible enough for the scrambling of
file transfers.
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