Transcript Presentation3

Department of Computer and IT Engineering
University of Kurdistan
Computer Networks II
IPTV
By: Dr. Alireza Abdollahpouri
Outline




Introduction and Motivation
IPTV System Structure
Basics of Video Encoding
Challenges
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Introduction and Motivation
 Television (TV) is a dominant and pervasive mass media
 The recently rapid growth of IP-based networks, and the trend
of network convergence
 The tremendous increase in real-time & multimedia
communications in Internet
 The advantages of TV delivery via IP-based network
IPTV
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Applications
Education: There have been some attempts to use regular TV as a medium of education. But regular
TV is unidirectional in nature. Taking advantage of the bidirectional capability of IPTV, it can be used as
an education environment especially in some developing countries.
Healthcare: Elderly people or people in remote locations (e.g., in rural area) cannot easily access
doctors for checkup or treatment. This problem can be solved by monitoring and treatment of patients by
means of IPTV (without need to leave the home) [2].
Financial services: Some people need instant access to business or financial developments and news.
Taking advantage of its bidirectional capabilities, IPTV can be used as a powerful tool in stock market
and television banking.
Instant feedback capability: Considering appropriate security and privacy options, IPTV enables the
people to play an instant role in voting and elections [2].
Travel and tourism: You are watching a commercial advertisement regarding discounts in ticket prices;
thanks to IPTV, you can book it immediately just by clicking the buttons on your remote control.
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Applications
Time Shift TV: enable stores feature and store any Broad
cast and can be seen at
any convenient time of the customer
• All Broadcast channel/live events (free as well as pay
channel)
•Video on demand (see any movies as per your choice)
•Video Conferencing
•Personalize advertisement and greetings
•DVD quality picture and sound
•Online training and video class
•Alert message for favorites programms- SMS alert and
many more…
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Overview: IPTV = (IP) + (TV)
 An emerging technology that delivers video, audio or TV
broadcasts over (IP) based networks with the required level of
QOS/QOE, security, interactivity, and reliability.
 In Conclusion: IPTV it means:
 Television you fully control
 Any content, any time, any place
 Television that can take you anywhere
 Unlimited visual interactive applications
 It’s the IP in IPTV that’s important!
 IPTV requires new technology in:
 Access networks
 Compression
 Middleware
 Customer premises equipment (CPE)
Services
 Live broadcasts: It's like watching live TV on your
computer screen. You can NOT pause, back up or skip
through parts of the broadcast that do NOT interest you.
 On-demand videos: Arranged like a playlist. Episodes or
clips are arranged by title or channel or in categories like
news, sports or music videos. You choose exactly what you
want to watch, when you want to watch it.
Coverage
Source: Wikipedia
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Outline




Introduction and Motivation
IPTV System Structure
Basics of Video Encoding
Challenges
9
IPTV System Structure
WiMAX
ASN
1
IPTV
Head-end
xDSL
Video
Source
VoD
Server
Core
Network
Metro
Backbone
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3
Access Network
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Customer Network
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IPTV Head-end Building Blocks
Each STB is assigned an IP address by the means of DHCP
IPTV
head-end
IGMP snooping
IP Multicast
STB 1
STB 2
STB 3
STB 4
ISP
IP backbone
Available C1
C2
TV
channels C3
C4
DSLAM
IP:172.24.200.17
Monitor station
(generates log file)
Using e.g., Tcpdump
Multicast in IPTV
IPTV
head-end
BRAS
DSLAM
ISP
IP backbone
STB
Multicast stream of channel X
Each channel
change involves
an IGMP leave and
an IGMP join
Watching channel X
IGMP leave (channel X)
IGMP join (channel Y)
Multicast stream of channel Y
Switch to channel Y
Watching channel Y
IPTV Head-end
Raw data
SDI
(270Mbit/s)
Video
Audio
MPEG2/4/H.264
Element Stream
(ES) (1.5-6Mbit/s)
MPEG2 or
H.264
Encoder
Video
Packetized ES
with header
(1.5-6Mb/s)
ES Packetizer
Video
(PES frame forming)
Audio
Audio
Encoder
ES Packetizer
Audio
(PES frame forming)
Data
PES A.V.D MUX
(Transport Stream
MPEG2/4/AVC
Encapsulated
Video stream
H.264/TS/RTP/UDP/
IP/Ethernet
MPEG-TS
RTP
Transport Streams
encapsulated into IP
(1.6-40Mb/s)
188 byte forming)
MUXed Multi
programs TS
(1.6-40Mb/s)
UDP
Single program
Transport
Stream
(1.6-8Mb/s)
Program 1
IP
Ethernet
TS encapsulated
into RTP/UDP/IP
Multi-program
MPEG TS
Multiplexer
Program 2
Program 3
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Core Network
 Central portion of an IPTV system
 Provides interconnection between several metro networks
 IP/MPLS and traffic engineering techniques
 Use High Capacity links (e.g., 10 Gbps)
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Distribution Network
 Serves a region or a metropolitan area
 Insertion of local content such as local TV
channels or commercial advertisements
 Provides on-demand video services to local clients
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Access Network
 Provides last-mile for IPTV
subscribers
 Can be based on wired
technologies (e.g., xDSL, FTTx) or
Wireless networks (High Speed WiFi,
WiMAX, LTE , 3G).
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Home Network
 Provides TV, IP phone and Internet (triple play)
services to subscribers.
 Connects to Access network
via a Home-gateway.
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Video reconstruction in STB
Decoder
MPEG DATA
Ethernet/IP/UDP/Payload
Socket
Payload
Buffer
Buffer
Video
Decode
Buffer
Audio
Decode
STB
PCR: Program Clock Reference
PAT: Program Association Table
PID: Packet IDentifier
PMT: Program Map Table
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Outline




Introduction and Motivation
IPTV System Structure
Basics of Video Encoding
Challenges
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Original Image (1153KB)
1:1
Spatial Redundancy elimination
Original Image (1153KB)
27:1
Original Image (1153KB)
192:1
Temporal Redundancy elimination
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An Example for Video Compression
Uncompressed
Compressed
Bit Rate= 4,562 Kbits/s
Bit Rate= 100 Kbits/s
Effect of packet loss
Single B frame packet loss
(only 1 frame affected)
Single I frame packet loss
(14 frames affected)
Impact 3.75Mb/s stream: B frame packet loss vs I frame packet loss
Source: Nortel
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Outline




Introduction and Motivation
IPTV System Structure
Basics of Video Encoding
Challenges
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IP multicast
DVMRP,PIM, MOSPF
Multicast forwarding
protocols
IGMP, MLD
Group management
protocols
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Distribution of TV Channel Popularity
Popularity
High p
1
7
13
19
25
31
37
43
49
55
61
67
73
79
85
91
Rank
97
Popular channel
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Popularity
Distribution of TV Channel Popularity
Low p
1
7
13
19
25
31
37
43
49
55
61
67
73
79
85
91
97
Rank
Unpopular channel
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TV channel classification
Favorite
Normal
Rarely watched
18000
multicast push
16000
14000
12000
10000
8000
Unicast
multicast pull
(on demand)
6000
4000
2000
0
1
7
13
19
25
31
37
43
49
55
61
67
73
79
85
91
97 103 109 115
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Zapping Delay in IPTV Systems (Reason)
IPTV
1-2 channels
Internet
VoIP
Last mile
(6 Mb/s)
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Zapping Delay in IPTV Systems
200 ms
Traditional analog broadcast
About 2 s
IPTV
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Zapping Delay in IPTV Systems
• The frequency of I-frames
• Reordering delay
• Size of video buffer in STB
• PAT and PMT frequency
• Multicast Leave and Join times
• The delay of access link
• STB jitter buffer
• Conditional access and digital rights management system
• Packet recovery with FEC/ARQ
• Processing time in the STB
• Processing time in display device
QoS and QoE
jitter
Head End
Home
Packet Loss
(Congestion, Link failure, …)
QoS
QoE
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Questions!
NOTES
Television has become an essential device in almost all the
houses across the world. Over the years, there have been
improvements in shape and size, in picture quality (standard
definition to high definition) and in the number of offered
channels. Despite all of these improvements, TV for a long
time remained a broadcast medium with one-way transmission
from the service provider to the end-user. Meanwhile, the new
generation of TV users, which have grown up with Internet and
interactive gaming are no longer satisfied with one-way
broadcasting of traditional TV systems.
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