Transcript Multimedia Communications

Standards for MM COMM
1
Interpersonal
2
Interactions over the Internet
3
Entertainment
4
Protocol Basics
5
A/V Conferencing in Circuit-mode
Networks
6
Audio-Visual Conferencing Standards
in Circuit-mode Network
7
T.120: Standards for User Data App.
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Media types
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T.124: sharing of text for what is known as text char
T.126: still-image and whiteboard sharing
T.127: sharing of file contents
T.128: sharing of text documents and spreadsheets
Communications
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T.122: MCU procedures
T.125: MCS procedures
T.123: a series of network-specific transport protocols
all of which provide a reliable transport service
8
Multiplexing
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Multiplexing of audio, video, and data streams
together for transmission over the network
H.221
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TDM: fixed portions of bandwidth are allocated
H.223
9
System Control
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H.242
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Negotiation of the bandwidth/bit-rate to be used for
each stream
Inform the multipoint controller part of MCU of its
capabilities (e.g. video format, A/V compression
standards, T.120 user data applications, proposed bit
rate of each channel)
Then, MCU negotiates and agrees a minimum set of
capabilities
H.245
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Exchange of messages for negotiation capabilities
Opening and closing of logical channels
Transmission of the contents of the multiplex table,
choice of adaptation layers
10
H.323: A/V Conferencing over Packetswitched Network
11
Call Setup procedure using H.323
Gatekeeper

H.323 gatekeeper
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Limit # of concurrent calls
to provide QoS quarantee
in LAN environment
12
H.323 multiplexing/demultiplexing
13
Interworking using an H.323 Gateway
14
IETF Interpersonal Communications
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SIP/SDP
15
E-mail over Internet
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SMTP, RFC 821
POP3, RFC 1939
IMAP
MIME (Multipurpose Internet Mail Extensions), RFC 2045
16
Protocol Stacks for email over
Internet
17
E-mail Gateway
18
Information Browsing
19
E-Commerce
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Network Security
PKI
20
Movie/Video-on-demand: telephony
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Movie/Video-on-demand: Cable TV
22
Interactive TV: Digital TV
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Video: MPEG-2
Audio: MEPG Layer 2
(PAL), Dolby AC3
(NTSC, ATV/GA)
TV Program Multiplexing
TS format
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