Internet HDTV and the ResearchTV Project.ppt

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1、Internet HDTV and the ResearchTV Project,Terry Gray University of Washington,Objectives for this talk,Briefly describe the ResearchTV project Focus on UWs Internet HDTV experiments Credits Corbat/ Zekauskas talk at I2/NLANR/JT Richardson talk at CANARIE workshop Philipson notes on ResearchTV,The Res

2、earchChannel,Formerly known as ResearchTV Distribution of HQ R&E videos Nationwide broadcast via Echostar Network distribution via Internet2 On-demand and scheduled Interested in HD and multicast Good QoS case study candidate! i2ResearchTV wg at March I2 mtg Participation and content welcome!,UW Net

3、work Environment,Pacific/NorthWest Gigapop vBNS OC3 Abilene OC12 (soon OC48) HSCC OC48 Commodity 4x DS3 Campus: separate GE R no ATM,UWs Internet HDTV Project,How would world change if it worked? Support ResearchChannel objectives Support Internet2 objectives Support our normal urge to push limits I

4、nterdisciplinary team from UW central computing organization Major assistance from Sony, lots of others Focus on studio quality HDTV and broadcast industry standards.,Chronology,Feb 99: Abilene roll-out (6 Mbps SDTV) Jul 99: HD/IP project kickoff Oct 99: I2 (Stanford to Seattle via Abilene) Nov 99:

5、SC99 (Seattle to Portland via NTON) Feb 00: ISIe-UW (DC to Seattle via HSCC),HDTV Basics,Movie-like images 16x9 aspect ratio, all digital, rich color sampling Many different flavors p vs. i, lines of resolution, sampling depth, etc. “1080i” = 1920x1080 60 interlaced fields/sec Quality levels: consum

6、er = 19.2Mbps contributor = 40Mbps studio = 200Mbps raw = 1.5Gbps,Video Data Rates,1.5Gbps Raw HDTV,270Mbps Uncompressed SDTV (SDI),200Mbps HDCAM Compressed HDTV,40Mbps MPEG2 HDTV Contribution,19.2Mbps HDTV Broadcast,HD/IP Block Diagram,UWs HD/IP Software,Two different projects: 40Mbps MPEG2-DVBASI

7、900B UDP datagrams RAID-style FEC; low latency Loss tolerance depends on decoder (5-10%) 200Mbps HDCAM-SDTI 1472B UDP datagrams retransmit and buffering; 4 sec latency Loss tolerance: 10-15% Using standard 1500 byte GigE MTU Not using RTP,Experiment 1: Fall I2 Mtg,Stanford to UW/Seattle via Abilene

8、OC12 40Mbps MPEG2-DVBASI stream 200Mbps HDCAM-SDTI stream Approximately 12 network hops Stanford, CALREN, Abilene, P/NWGP, UW Sony provided an HDTV movie projector Jay Leno, Secret Adventures of Jules Verne,Abilene - afternoon of UW event (2 hour average),Experiment 2: SC99 GNAP Demo,UW/Seattle to P

9、ortland via NTON OC48 Five concurrent 200Mbit streams 1+ Gbps 4 streams sourced from disk arrays 1 stream sourced from Sony HDTV system (live and tape) All streams displayed concurrently at SC99 Link shared with MSR desktop Gbps TCP demo 2.4Gbps sustained; 54.7 Terabytes in 90 hours! Overall packet

10、loss observed: 10-4 - 10-5 predominantly at application and system layers,SC99 GNAP Booth,15-18 November, 1999 Portland, Oregon,SC99 Flows,Experiment 3: ISIe/UW,ISI/DC to UW/Seattle via HSCC OC48 Single GE router attachment 200mbps HD + 700mbps chaff = 900 total 700 chaff: high LOCAL loss 700 chaff:

11、 low loss (.0005%) Soon: 5x200 HD/IP via two GE ports,HSCC iperf UDP tests,UW-ISIe: 100-475 Mbps consistent 0.03% loss ISIe-UW: 100 Mbps 0.003% 200 Mbps 0.03% 400 Mbps 0.2% 600 Mbps 0.2%,Next Steps,Pushing the system: uncompressed HDTV, multi-stream servers Studying the system: understanding the bot

12、tlenecks, exploring latency vs. quality Scaling the system: QoS, multicast, different data rates, VBR encoding Using the system: TV production, visualization, medicine, teleconferencing,QoS Issues,Limits of application error correction TCP v. UDP issues Impact of CBR vs. VBR encoding Impact of DiffS

13、erv Impact of MPLS and DWDM Impact of Multicast,Conclusions,Studio HDTV to your home is NOT imminent Studio HD/IP is viable, without dedicated links Gbps flows are sustainable in the I2/NGI space Gigabit networking and e2e performance are NOT solved problems (especially for TCP) Network ops: Be very

14、 afraid & go to SNMPv3 SNMPv1 counters wrap every 13seconds at OC-48c,References,ResearchTV/ResearchChannelwww.washington.edu/researchtv Internet HDTV projectwww.washington.edu/hdtv Enterprise QoS Survival Guidestaff.washington.edu/gray/papers Gigabit Networking & Applications Partnership - GNAP:UW, Sony, ResearchTV, P/NW Gigapop, Microsoft, NCSA/Alliance/NLANR, NTONC, DARPA Additional help from: Stanford U, Juniper Networks, Qwest, U S WEST, Nortel, GST, Alcatel/Packet Engines, Alteon, SysKonnect, SC99, Oregon State U, Sandia-Livermore, ISIe, UCAID,