f9c63666827f6a3f0f4ab2fa1ca8a146.ppt
- Количество слайдов: 19
Internet Protocol Television YOU ARE WATCHING IPTV The Future of Television
IPTV: Background Digital TV service delivered using IP TV content received by viewer through network technologies Usually bundled with Internet services such as Web access and Vo. IP
IPTV vs. Internet TV Control over delivery enables a guaranteed Qo. S n Allows service provider to offer enhanced user experience Internet TV refers to transport streams sent over IP networks from outside the network that connects to user Internet TV provider has no control over final delivery n Broadcasts on "best effort" basis Elementary streams over IP networks (ex You. Tube) are NOT considered IPTV
IPTV: Delivery Methods Delivery as a file transfer (FTP/Bit Torrent) Broadcast (Live TV) Video on demand (VOD) Broadcast & VOD for real-time viewing
IPTV: Broadcast Each feed provided unique channel number Establish multicast connection Eliminates need for all digitized channels to flow into homes Each source is input into broadcast encoder Packetizes the video stream Servers support delivery of multicast and unicast VOD response flows as sequence unicast datagrams
IPTV: Protocols Compressed using MPEG-2 or MPEG-4 codec Delivered via : n n IP Multicast Live TV IP Unicast Video on Demand IP Multicast Info simultaneously sent to multiple computers Live TV: IGMP connecting to multicast stream and changing from one multicast stream to another VOD: Real Time Streaming Protocol (RTSP)
IPTV: Underlying Protocols Real-time Transport Protocol (RTP) n Defines standardized packet format Real-Time Transport Control Protocol (RTCP) n n n Provides info about participants in ongoing session Mechanism to monitor the quality of service Operates via periodic transmission control packets
IPTV: Transport – UDP/RAW Video can be transported in UDP packets without RTP Transport stream referred to as UDP/RAW Error/informational conditions can be detected: n n n Sender changed Missing synchronization bytes Incorrect packet size Time-outs Excessive jitter Improper UDP bit rate
IPTV: Transport – UDP/RTP can compensate for error conditions UDP/RTP enables receiver to: n n Determine if packet is lost Can compensate for the occurrence of lost packets Time stamp enables receiver to: n n n Perform synchronization Resolve jitter due to delays Detect several additional error conditions
IPTV: Enhanced User Experience Interactive program guide Picture-in-picture functionality Look up a player’s stats watching sports Change camera angle Access photos/music from PC on TV Use cell phone to schedule recording
IPTV: Benefits Ability to integrate TV with other IP-based services (ex. high speed Internet and Vo. IP) Delivery of more content and functionality Only content customer selects sent Frees up bandwidth Customer’s choice less restricted by ‘pipe’ size
IPTV: Drawbacks Customer's privacy could be compromised Provides a means to hack into or disrupt (ex. Do. S attacks) the private network Sensitive to packet loss Sensitive to delays if connection not fast enough Troublesome streaming across wireless links
IPTV: Jitter Concerns Problem: displacement of packets Referred to as jitter Solution: jitter buffer at receiver Memory used to compensate for delays Packets enter receiver’s jitter buffer Extracted at applicable times
IPTV: Screenshot
IPTV: Major Players BT Vision Internet television Joost Continuous Computing Microsoft Mediaroom NOW TV P 2 PTV Live. Station Zattoo IP Triple Play
IPTV: Future Expected to grow Biggest challenge is integration with core network Better manage tech already in customer's domain Long-term stability Personalized TV IPTV with NGN n Next-Generation Network (NGN) network handles heavy traffic n Enables content providers to deliver heavy media content across network Killer app for Next Generation Internet? ?
Citations Marcio Nieblas Zapater, Graca Bressan, "A Proposed Approach for Quality of Experience Assurance of IPTV, " icds, p. 25, First International Conference on the Digital Society (ICDS'07), 2007 Jay Kishigami, "The Role of Qo. E on IPTV Services style, " ism, pp. 11 -13, Ninth IEEE International Symposium on Multimedia (ISM 2007), 2007 Yuzo Iano, Marcus Pereira Magri, "How to architect an IPTV system, " wiamis, p. 53, Eight International Workshop on Image Analysis for Multimedia Interactive Services (WIAMIS '07), 2007 Benjamin Alfonsi, "I Want My IPTV: Internet Protocol Television Predicted a 'Winner, '" IEEE Distributed Systems Online, vol. 6, no. 2, 2005.