Presentation on theme: "IPTV: Becoming a reality Pierre Thiry CNIT Instructor ICONS P.I."— Presentation transcript:
IPTV: Becoming a reality Pierre Thiry CNIT Instructor ICONS P.I.
Outline Cable TV system: –Live TV : Radio Frequency channels –Video-on-demand: DVB (Digital Video Broadcasting) Definition of IPTV : free and fee-based How fee-based IPTV works: –Encoding at the head end:MPEG2 & MPEG4 –IP packets –Distribution and Reception: Live TV: IGMP v2 Video-on-demand: RTSP –Challenges and present state in the US
How present cable TV works Live TV needs a tuner to select the proper channel Video on demand uses the Digital Video Broadcast (DVB) protocol Cable TV uses fiber-optic cable to transmit to the neigborhood and use coaxial cable to connect to the home
Definition of IPTV: Free IPTV Free IPTV: according to Wikipedia, as of June 2006, there are over 1,300 free IPTV channels available. All you need is an Internet connection and a PC, an iPOD or a 3Gcell phone with the proper streaming software Most TV stations have now a Free IPTV web site
Video Compression formats: MPEG-1 (Video CDs) progressive Data rates were limited to 1.8 Mbps (1996) (MP3 is the audio encoding of MPEG-1) MPEG-2 (DVD, Digital TV) interlaced Data rates are from 1.5 to 60 Mbps (2000) Two container formats: Transport Stream: for broadcasting (ASTC & DVB) Program Stream: for DVD abd Super Video CD
Video Compression formats: MPEG-4 (All Inclusive and Interactive) based on Quicktime, including low-bandwidth formats for transmitting to wireless devices as well as high- bandwidth for studio processing. MPEG-4 AAC (advanced audio coding) is widely used as an audio-only format (replaces MP3) MPEG-4 AVC (or H.264) is the new standard for video transmission.
Distribution & Reception Multicast protocol: from national headend to the local office: needs powerful routers Bottleneck at the local office: oDSL is limited in bandwidth (up to 3Mbps) oThe new ADSL+ will go up to 25Mbps Solution: use IGMP v2 from the set-top box to ask for a given channel. The set-top box is an IP receiver.
Quality of Service Between the headend and the local office: Error correction mesures for the multicast streams Between the local office and the set-top box: since it is unicast, it is not a problem, the system can request a resend of lost packets.
IPTV Video-on-demand Real Time Streaming Protocol enables DVD-style control (pause, fast forward..) over a multimedia stream. Limit on the number of simultaneous channels: –For SDTV maximum of 10 channels –For HDTV maximum of 2 channels if MPEG-2 is used. More if MPEG-4 is used. Advantage of the fiber to the home.
Example of IPTV abroad Hong Kong and China: PCCW http://en.wikipedia.org/wiki/Pacific_Century_ Cyberworks http://www.nowbroadbandtv.com/eng/ More than 300,000 subscribers
In the US: AT&T and Verizon AT&T – project Lightspeed : 40,000 mile rollout of fiber. Not all the way to the home. ( limited by ADSL performance 3Mbps) Verizon offer 300+ channels of TV over Fiber to the home ( 4.5 Gbps – 3.5 Gbps for TV )
Telco vs Cable Telco have won recently a battle from the FCC to allow franchise agreements to be negotiated by state. If Telco companies can compete with the cable that will mean cheaper services for the customer. Cable companies are looking also at IP to upgrade their services.