Your SlideShare is downloading. ×
Internet TV
Upcoming SlideShare
Loading in...5
×

Thanks for flagging this SlideShare!

Oops! An error has occurred.

×
Saving this for later? Get the SlideShare app to save on your phone or tablet. Read anywhere, anytime – even offline.
Text the download link to your phone
Standard text messaging rates apply

Internet TV

2,065
views

Published on

Lectures from the broadcast multimedia course held in TUT

Lectures from the broadcast multimedia course held in TUT


0 Comments
2 Likes
Statistics
Notes
  • Be the first to comment

No Downloads
Views
Total Views
2,065
On Slideshare
0
From Embeds
0
Number of Embeds
1
Actions
Shares
0
Downloads
137
Comments
0
Likes
2
Embeds 0
No embeds

Report content
Flagged as inappropriate Flag as inappropriate
Flag as inappropriate

Select your reason for flagging this presentation as inappropriate.

Cancel
No notes for slide

Transcript

  • 1. Internet TV – Yet another TV ?? Broadcast Multimedia course – TUT - 2008 Adrian Hornsby
  • 2. Short on Internet Internet  − world's largest computer network − collection of smaller networks, computers, and people who use them. − around 28 million people Until recently, multimedia and internet were not  really going together − Not enough bandwidth, load, errors, traffic ...
  • 3. Yet another one ... Digital Media Revolution … • Huge increase in media content • Faster communications • New user experience • New consumer demand New digital devices + new digital transmission systems = New digital transmission system 10/29/08
  • 4. Yet another TV system !!! Internet Television (TV), iTV  − Television like content distributed through the internet. Running on existing IP infrastructure (DSL, Wifi, 3G data ...)  Distribution model  − Live Streaming − VOD − But also P2P (P2PTV)
  • 5. Tell me more ... Differ from IPTV  − Not a dedicated network but over the internet No real QoS  − Does not require set-top box − Provider not always clear Legal and none legal content  − Quick to market with Low investment cost − Usually uses advertisement as main revenue
  • 6. And how does that one works ?? Browser + media player (plugins)  − No special equipment, just a computer and a connection to internet Several options ...  − HTTP streaming (basic and advanced flavor) − RTP based multicast streaming − RTSP based streaming
  • 7. HTTP streaming ? hmm ... (basic flavor) Simplest and cheapest way to stream video  from a website No special type of website or host  − recognizes common video file types Good option for websites with modest traffic  No live video  − HTTP method needs complete files stored on the server. − No automatic detection of end user's connection speed different file for different speeds 
  • 8. HTTP streaming (basic flavor) HTTP-like live streaming  1- Clients request with HTTP-Get message 2- Server replies with a HTTP-OK response 3- ... continuous stream of data (usually port 8000) 4- Also referred as HTTP-push long-lived HTTP connection.  keep the connection open by running a long loop 
  • 9. HTTP streaming basic flavor Web Browser HTTP meta file Web HTTP content Server Media Player
  • 10. HTTP streaming (advanced flavor) Similar to basic flavor except media sent by  specialized streaming media server − Data delivery process differs No passive http push technique  Data send actively and intelligently,  − eg. data rate associated with compressed media streams Server and client in touch, responses to feedbacks  Stream usually controlled by ZeroWindow / KeepAlive  mechanism − Receiving host use the window field in each acknowledgment to inform the sending host how much more data it can receive [rfc793],0 if receiver is pausing the stream. When playing resumes, the receiver sends another ACK with a nonzero window size.
  • 11. HTTP streaming (advanced flavor) Web Browser HTTP meta file Web Server Media Player HTTP media content Streaming Server
  • 12. ... hmm I prefer advanced flavor ! More efficient network throughput  Better audio and video quality  Support for advanced features  Larger number of users  Content copyright handling  Multiple delivery options 
  • 13. HTTP streaming servers example Basic flavor  − Apache Special flavor  − Shoutcast − Icecast − VLC − Window media server
  • 14. RTP-based streaming So called multicast streaming  − requires global multicast address (€€) − No subscription subscription Combining RTP over UDP  More for Live events, no “real” control on  stream
  • 15. Real-Time Transport Protocol (RTP) (optional) RTP packet (V) RTP Compressed video header RTP Profile RTP packet (A) RTP IP UDP RTP Compressed sound header RTCP packet (C) (option) RTP Sender/Receiver report header UDP packet RTP Profile UDP IP UDP RTP header
  • 16. How does my device access the media stream ?? Listen SAP announcement (default 224.2.127.254:9875)  SDP1 SDP2 SDP3 SDP4 SDP5 SDP6 SDPn Access SDP (Service Description Protocol)  v=0 o=QTSS_Play_List 1460227057 502868560 IN IP4 130.230.50.48 s=stream-32 c=IN IP4 239.252.80.5/1 b=AS:375 t=0 0 a=x-broadcastcontrol:RTSP m=video 5004 RTP/AVP 96 b=AS:248 a=rtpmap:96 MP4V-ES/90000 a=control:trackID=1 a=cliprect:0,0,240,320 a=fmtp:96 profile-level-id=1;config=000001... a=mpeg4-esid:201 m=audio 5006 RTP/AVP 97 b=AS:127 a=rtpmap:97 mpeg4-generic/44100/2 a=control:trackID=2 a=fmtp:97 profile-level-id=1;mode=AAC-hbr;...; a=mpeg4-esid:101
  • 17. RTP streaming Web Browser HTTP Web SAP/SDP meta file Server Media Player RTP media content Streaming Server
  • 18. RTSP based streaming For media on demand-like Internet TV  PLAY PAUSE STOP RTP
  • 19. RTSP streaming Web Browser HTTP meta file Web Server rtsp://example.org/example/current.rm RTSP commands Media Player Streaming RTP media content Server HTTP media content (rare) RTSP may also be combained with HTTP streaming !!
  • 20. RTP/RTSP streaming servers example VLC  Darwin  Windows Media Server  Helix  Live555  Feng 
  • 21. Business Model Free  Pay per clip, per time  Ads  On demand / Live  Open / Proprietary (downloadable player)  Central / Distributed / P2P 
  • 22. Internet TV and some limitations ... − Internet network − No QoS − Bandwidth issue − Poor Audio Video Quality − Interrupted Delivery − Content protection − Long Channel Zapping − Poor content − Advertising !!
  • 23. Internet and multicast ... Broadcast Multimedia course – TUT - 2008 Adrian Hornsby
  • 24. Short on Internet (remake) Internet  − world's largest computer network − collection of smaller networks, computers, and people who use them. − around 28 million people Until recently, multimedia and internet were not  really going together − Not enough bandwidth, load, errors, traffic ...
  • 25. Internet and multimedia First with emails @, files ...  Then FTP and Gopher ...  Tradition of sending in one-to-one model (unicast) Recently .. explosion of digital information  Pictures, Videos, Presentations ...  Need for real-time multimedia communications  One-to-many − Bye bye unicast − Welcome multicast over the internet !!
  • 26. Internet and multicast ... Early 90's: The Multicast Internet (quot;the MBonequot;) − region of public Internet connected by IP Multicast Critical piece of the technology needed to make multiple-person data, voice, and video conferencing on the Internet -- in fact, sharing any digital information -- cheap and convenient. [http://www.savetz.com/mbone/ch3.html]
  • 27. Mbone .... Virtual network on top of the Internet  Invented by Van Jacobson, Steve Deering and Stephen  Casner in 1992. Minimize the traffic for shared AV conferencing  MBONE is free  − Unix based network of mrouters that support IP Multicast − enables access to real-time multimedia on the Internet tunneling protocol  − encapsulated multicast packets in unicast packets 224.0.0.0 - 239.255.255.255 
  • 28. Mbone in the world ...
  • 29. But it no longer exist ... Multiprotocol Extensions for BGP (MBGP)  − IETF RFC 2858 − allows different address families to be distributed in parallel − exchange of inter-domain multicast routing information − Uses PIM to build trees and forward multicast traffic.
  • 30. M6bone What is it ??  − An IPv6 Multicast test network − M6Bone started in July 2001 − 24 networks & 45 sites Goals  − Offer IPv6 Multicast connectivity − Test and develop Ipv6 Multicast − Standardization and recommendation − Deploy advanced service on Ipv6 http://www.m6bone.net 
  • 31. Connections schemes More details online at http://www.m6bone.net/article.php3%3Fid_article=55.html
  • 32. Applications Mbone tools: sdr, vic, rat, nte, wb  Freeamp patches (mp3/rtp)  MIM (mpeg-1/mp3 over rtp)  ttcp and iperf  Multicast beacon (written in java), just worked for ipv6  Available content Misc vic/rat sessions  TUR (Trondheim Underground Radio)  NRK (Norwegian national broadcasting) radio channels  All global IPv4 multicast sessions (through gateway)  Maybe this time will be a success !!
  • 33. Thanks ...
  • 34. Open Discussion !! Can Internet TV replace traditional TV ?  What business model ?  All Internet ?  ....  Other questions ? 