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, - , , DVB/MPEG- IP-.
- : , , , .. . (CAS) , STB . STB STB .
, multicast IP-, ( ) . MPEG-2- 4 /. , MPEG-2- 3 /. . MPEG-4-ABC , . , , IP- - . VC-9 Microsoft , , Microsoft.
unicast- ( ) MPEG-2- . , - VoD (3,75 /) .
, MPEG-4 : 2 / multicast- 1,7 / unicast-.
, 5 . , IP-, , MPEG-2, (VBR-) IP- 15...20 /. , .
IP- (), , ATM (IP video over ATM) Ethernet, SDH-. - , , IP- .
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DVB-S, DVB-ASI- , , (SPTS) (MPTS);
, SDI, S-video, , DVI (Digital Video Interface) HDMI (High-Definition Multimedia Interface);
DVB-ASI- DVB-- , ;
, IP (MPEG over IP), Video over ATM, IP-video over ATM.
DVB-ASI (SPTS/MPTS) . IP-. , IP- , IP- IP- ( ). , IP-, -IPTV.
, , , . SPTS/MPTS- IP-, . , - . , . , , , 500 . , . , MPEG- . , - . , , . , DVB- MPEG- , , , :
DVB- , DV - , ;
MPEG-, . , , . , : , () IP-;
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MPEG- IP- - ( , MPEG-4 MPEG-2 , , ..). , , .. .
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IP-encapsulation (IP-) , MPEG- PDU (Protocol Data Unit), Gigabit Ethernet, SDH ATM;
Transrating () () , reteshaping;
Transcoding () , , MPEG-2 MPEG-4;
Encoding () MPEG-2 (4) VC-1/ Windows Media VC-9 ( , , S- , SDI);
Decoding () , ;
Re-encoding (-) ( , .. );
Scrambling () , (AS);
Descrambling () , .. ;
Multiplexing remultiplexing () (SPTS) / (MPTS) (MPTS), PSI-; , , ;
De-multiplexing () , ;
Statistical multiplexing ( ) MPTS-, (up-link); , , MPTS-, (VBR). , - ( DSL ) ;
PSI redaction (PSI, Program Specific Information );
NIT (Network Information Table), ;
(Program Map Table), SDT (Service Descriptor Table), NIT (Network Information Table) CAT (Conditional Access Table);
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( ) , IP- , IP-. MPEG- IP 188- MPEG- PDU (Protocol Data Unit). (Header) (Trailer) .
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MPEG-2 MPEG-4 MPEG-4 MPEG-2?
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(DSL, Ethernet, ATM, SDH, , );
MPEG-2 MPEG-4-;
MPEG-2 MPEG-4-;
DVB AS / IP CAS.
IP- :
(+1, 1+1), ;
, ;
.
IP- IPTV Head End. - : Tandberg Television, Scientific Atlanta, Scopus Video Networks, Terrayon Communication Systems, Optibase.