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ECEN5553 Telecom Systems Dr. George Scheets Week 15 & 16 Read [36a] "Dish network for the enterprise" [36b] "Lighting up Copper" [36c] "Bell Labs Claims New Speed Record Over Old Copper Wiring" [37a] "IPTV and Video Networks in the 2015 Time Frame: The Evolution to Medianets" [37b] "Netflix Factor has University Networks Creaking Under Streaming Video Strain" [38] "The Broadcast Empire Strikes Back" Final Exam Friday, 11 December, 1400 – 1550 (Live) < 18 December (Distance Learning)
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Comprehensive Final Exam n Everything from Day 1 is testable u Notes u Power Point slides u Required Readings n Work 5 of 7 pages on final. u 2-3 pages will be from last year n Address the question n Use the space provided u Give the instructor the feeling you could've said more! u Rule of thumb: Provide > one fact per point
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MPEG 1 n n Standard since 1992 n n Compression of motion video & audio at about 1.5 Mbps (VHS Quality < NTSC) n n Targeted at digital playback & storage n n Has Random Access capabilities n n Somewhat Obsolete n n Divides picture up into 8x8 pixel blocks Converts blocks to bit stream
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MPEG 2 n n Targets higher quality compression, typically at 3-6 Mbps bit rates n n Being used for Direct Broadcast TV n n Large chunks of MPEG2 used in U.S. HDTV standard n n Standard since 1994 MP3 n Web audio clips n Uses audio compression from MPEG 1 u 12-1 typical compression ratio
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MPEG 4 n n Aimed at Multimedia Coding n n Bit rates from 8 Kbps - 40+ Mbps n n Can codes objects as opposed to NxN blocks u u Ability to interact & manipulate objects n n Standard in 1999 n n Used in Quicktime 6, Direct TV
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H.261, H.263, & H.264 Target real time videoconferencing Subset of MPEG Wide variety of bit rates 64 Kbps - 128 Kbps: Face shot (video phone) 384 Kbps: considered to be minimum speed for decent full screen videoconferencing New OSU gear is using H.263/4 @ 1.92 Mbps H.264 quality > H.263 > H.261 Newer protocols require more processing power H.261 less common today
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Thermal Noise Power in 6 MHz n 70 degrees Fahrenheit? u ≈ 24.01(10 -15 ) watts n 32.3 Mbps → Channel Capacity says SNR needs to be > 40.64 u Need Signal Power > 975.8(10 -15 ) watts out of receiving antenna n Analog NTSC required SNR ≈ 15,800… u … for a good quality picture u Needed Signal Power = 379.4(10 -12 ) watts out of receiving antenna
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Video Delivery: Over the Air 300 m ATSC Digital FDM Since June 2009 (FCC edict) 40-50 miles
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Video Delivery Systems n n Geo-Synchronous Satellite Analog NTSC (Obsolete) u u 1 channel per 6 MHZ of RF bandwidth u u 10 foot satellite dish Newer Systems digital MPEG2/4 u u Can get 4-6 "NTSC quality" SDTV channels per 6 MHz of RF bandwidth (TDM) u u 1-2 HDTV signals per 6 MHz RF bandwidth u u 18 inch satellite dish u u MPEG4 = same quality, fewer bps
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Video Delivery Systems n n Cable TV u u Tree configuration u u Distribution systems originally all coax u u Originally Analog NTSC u u BW ≈ 700 MHz Headend AMP... AMP... Initially Simplex Copper Coax
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Video Delivery Systems n n Cable TV u u Tree configuration u u Fiber deployed from Head End side moving out Headend AMP... AMP... Copper Coax Fiber 2nd Generation Hybrid Fiber Coax a.k.a. FTTx
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Video Delivery Systems n n Cable TV u u Now mostly digital ATSC, MPEG2/4 u u Cable Modems require 2-way commo F F Some 6 MHz channels pulled from TV pool Headend AMP... AMP... Copper Coax Fiber 2nd Generation Hybrid Fiber Coax FTT curb
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Video Delivery Systems n n Cable TV u u Ultimate Goal: Fiber to the Home (FTTH) u u Passive Optical Network F F No active electronics in access network Headend Splitter... Fiber 3rd Generation FTT home... Splitter... Splitter
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Representative Video Bit Rates (Hi ↓ Lo Quality) n 1.2 Gbps Uncompressed HDTV n 19.4 Mbps ATSC ( ≈ HDTV quality) n 8 - 9 Mbps MPEG4 ( ≈ HDTV quality) n 90 Mbps Uncompressed NTSC (SDTV) n 3 - 6 Mbps MPEG2 ( ≈ SDTV quality) n 1.5 Mbps MPEG4 ( ≈ SDTV quality) n 1.5 Mbps MPEG1 ( ≈ VHS < SDTV quality) n How Much More Compression is Still Possible? u H.264 uses 30% less bits than MPEG4 F November 2008 IEEE Communications Magazine
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Compression n Requires a Signal with Redundant information u Must be some predictability n Compressing a Signal u Makes Result Less Redundant n You can't compress forever n Information Theory u Math that puts bounds on amount of compression
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Last Mile Options for Home & SOHO Mbps for Data & DTV n Dial up Modems u Pathetic BW n Point-to-Point Wireless u WiMax, WiFi, Proprietary n Satellites u GEOS, LEOS n Power Lines u Possible in Europe, Not economical in U.S. n Cable Modems
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PSTN 33.6 Kbps Dial-Up Modem Server CO 2 Wire ‘4 Wire’ Modem Protocol Digital TDM (1's & 0's) 64 Kbps n CO Input Line Card Low Pass Filter limits BW (3 - 3.5 KHZ) u M-Ary Signaling (256 QAM or something even more complex) n Channel Capacity says max transfer is around 35 Kbps PC Modem Protocol
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56 Kbps Modem requires Digital Source Server CO PC Digital TDM 1's & 0's (ISDN, T Carrier, SONET, OTN) Discrete Voltage (128 possible values) (7 bits, 8000x/sec) PC to Server traffic will be slower, similar to previous slide. CO Modem Bank ISP Digital StatMux 1's & 0's
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Dial Up: PC to ISP Connectivity CO Voice Switch Local Loop Home Modem ISP Modem Bank To Internet This configuration used to cause call blocking problems at some CO switches due to longer than designed-for call holding times. Voice network PC
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n Fine print indicates u Uses Acceleration (compression) u Some material won't be compressed u Actual data transmission rates = standard dial up rates
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Last Mile Options to the Home n Point-to- Point Microwave u Cellular type technology u Fixed sites using directional antennas
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Last Mile Options to the Home n Geo-synchronous Satellite u High Speed down links u Very Slow Speed Phone Line ‘up link’ Server ISP Phone
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Last Mile Options to the Home n Geo-synchronous Satellite u High Speed down link u Not-so-High speed up link Server
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Hughes Net (2013) @ 15 Mbps, to go full blast need TCP Window = 15 Mbps*RTT = 15 Mbps*0.5/(8 b/B) = 937.5 KB (Sat uplink & downlink)
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Last Mile Options to the Home n Low Earth Orbiting Satellite u Teledesic 2004? 2005? Never! u 300+ Kbps u Cellular type technology Cells Move Earth units ‘fixed’ RIP
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Last Mile Options to the Home n Point-to-Point Laser u Currently proprietary. Up to 2.5 Gbps speeds. u Aimed at Businesses n Leased Lines (a.k.a. Private Lines) u Expensive u Aimed at Businesses n Power Lines u Not as currently configured on MAN u Usable in home LAN
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Powerline HAN 10/100BaseT Ethernet: PC ↔ Adapter 500 Mbps: Adapter ↔ Adapter
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Last Mile Options n n Cable Modem Network (DOCSIS) u u Simplex 6 MHz downstream channels u u Simplex 200 KHz to 6+ MHz upstream channels u u All traffic traverses the Headend Headend AMP... AMP... Copper Coax Fiber 2nd Generation Hybrid Fiber Coax FTT curb
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Cable Networks n Have a Lot of BW (XXX MHz) n Allocate 6 MHz channels for various services u FDM n 6 MHz Channel can carry u 2 MPEG4 HDTV signals u 3-6 MPEG2/4 SDTV signals u 30-40 Mbps Cable Modem Traffic DOCSIS (Data over Cable Service Interface Specification) F Internet F VoIP
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Cable Modem Connectivity Headend Voice Switch Cable TV Network Home ISP Router To Internet Cable Modem uses shared bandwidth to get to Cable TV Headend. Voice network Mux Legacy Voice Data IPTV VoIP PC Cable Modem Voice Legacy Video PC
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Cable Modems n Use FDM 6 MHz channels u Ethernet Frames mapped to QPSK or QAM RF signal u 30 - 40 Mbps downstream u 320 Kbps to 30 Mbps upstream n Downstream u Head End controls use u TDM time slots, possibly assigned for a very short duration n Upstream u Head End assigns frequency band to end users (FDM) u Head End assigns time slots (Vendor specific algorithms) F Long term assignments (TDMA-like) F Short term assignments (StatMux-like)
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Last Mile Options n n Digital Subscriber Line (xDSL) u u Rides on top of Telco access network u u Runs over twisted pair cabling u u Various flavors exist CO...
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ADSL Connectivity CO Voice Switch Local Loop Voice (analog) Data (ATM) ISP Router To Internet ADSL off loads data traffic from CO voice switches, & provides more CO↔Home bandwidth. Voice network DSLAM Legacy Voice Data Home PC ADSL Modem Voice PC Splitter Data IPTV
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ADSL n Plain Vanilla ADSL u 384 Kbps - 8 Mbps downstream u 16 Kbps - 640 Kbps upstream n Uses FDM u POTS analog voice stays in 0 - 4 KHz band u Upstream and Downstream signals mapped to higher frequency bands F Uses OFDM u ATM or Ethernet frame formats F To & From CO
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Some of the Flavored Versions n ADSL2 u Needs higher SNR than ADSL u 8 -12 Mbps downstream u 800 Kbps - 3.5 Mbps upstream n ADSL2+ u Doubles used Bandwidth & Bit Rates u Can also bond multiple twisted pairs Inverse Multiplex n VDSL2 u 4 - 8 MHz BW, Inverse Multiplexing u 100 Mbps over short distances
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Asymmetric Digital Subscriber Line n Can carry u A handful of 1.5 Mbps SDTV signals u Internet traffic (in left over BW) u Standard voice call u 0 HDTV signals n ADSL2+ potentially can carry 2 HDTV channels u Two 9 Mbps MPEG4 n To Support Triple Play Service u TelCo's need to drive fiber down towards homes u FTTH: Gbps speeds possible u VDSL2+ can support 100 Mbps on copper out to 1/3 Km
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DSL Speeds source: www.convergedigest.com/blueprints/ttp03/bp1.asp?ID=232&ctgy=Loop (Copper)
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(Triple) Double Play Provider n 100 Mbps minimum BW u Voice u Several Mbps for Data u Several HDTV Channels F May not be enough for 3D HDTV n Advantage Cable TV providers u More BW available n May change depending on FTTH u Who get's there first?
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Video Delivery Systems n n Telco Digital Subscriber Line u u Ultimate Goal: Fiber to the Home (FTTH) u u Passive Optical Network F F No active electronics in access network Central Office Splitter... Fiber 3rd Generation FTT home... Splitter... Splitter
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IPTV & ISP Backbones IPTV & ISP Backbones nn1nn150 HDTV MPEG4 TV channels uu1uu1.45 Gbps of traffic to move uuSuuStatMux, need ≈ 2.9 Gbps trunk capacity uuTuuTwo OC-48's uuNuuNot a show stopper FFEFFEspecially using multicast One video stream services many customers nnVnnVideo on Demand uuCuuCould be a problem uuOuuOne video stream may service one customer
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IPTV & Last Mile Networks n On the Access Network u Cable TV/Cable Modem: No Problem u FTTH : No Problem u xDSL: Problem F Unless Next Door to CO F Or near FTTC termination F Either way, can't stream 150 HDTV channels F Solution: Selectively feed a few n On the Home Network u 100 Mbps can handle several HDTV channels u Leaves significant BW available for data & yet-to-be-invented apps
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150 HDTV Channels? n n Cable TV/Modem Network u u 150 HDTV Signals over 75 RF Channels (450 MHz) F F Simulcast (2 TDM over each 6 MHz FDM) u u 1.2 – 1.6 Gbps (250 MHz) available for data Headend AMP... AMP... Copper Coax Fiber 2nd Generation Hybrid Fiber Coax FTT curb
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Delivering 150 HDTV Channels n n Fiber to the Home (FTTH) Passive Optical Network (PON) u u BW in the THz u u Shared via WDM, TDM, TDMA CO or Headend Splitter... Fiber... Splitter... Splitter
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Delivering 150 HDTV Channels n n Digital Subscriber Line (ADSL) u u Can't do it. BW ≈ XX MHz (lower double digit) u u At best, can simulcast 2 with ADSL2+ CO... Twisted Pair
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n n Fiber to the Curb & VDSL2 u u Can't do it u u 100 Mbps over last 1,000 feet F F Could selectively stream an extra channel or two F F Active electronics required on last segment Delivering 150 HDTV Channels CO Splitter Twisted Pair Fiber FTTC... VDSL2... VDSL2
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IPTV - Replacement for Cable TV? n On the ISP Backbone u 150 MPEG4 HDTV Channels u Not a show stopper n On the Access Network u Cable TV/Cable Modem: No Problem u FTTH: No Problem u xDSL: Problem F Unless Next Door to CO or FTTC terminal F Still won't be able to stream all 150 channels
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IPTV on the Access Network ISP Backbone User TV User TV User TV User TV Local Cache... n n Regional Caches u u Streamed All or Most TV Network Programs n n Local Cache u u House Apartment Complex u u Streamed > 1 channel, Access BW permitting. n n User TV u u Streamed > 1 channel, Home BW permitting. Regional Cache...
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IPTV on the Access Network ISP Backbone User TV User TV User TV User TV Local Cache... n n Want to change channel? n n TV Cache Checked u u Available? < 1/2 second to change u u Not available? Packet request shipped to Local Cache Regional Cache...
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IPTV on the Access Network ISP Backbone User TV User TV User TV User TV Local Cache... n n Local Cache Checked u u Available? Channel streamed to TV May take > 1/2 second u u Not available? Packet request shipped to Regional Cache Regional Cache...
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IPTV on the Access Network ISP Backbone User TV User TV User TV User TV Local Cache... n n Regional Cache Checked u u Available? Channel streamed to Local Cache, then user TV. u u Not available? Packet request might need to be shipped to info source. u u If these are busy... Regional Cache...
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IPTV on the Access Network ISP Backbone User TV User TV User TV User TV Local Cache... n n Channel Change May Take Several Seconds n n Channel Surfers Won't be Happy n n Ongoing Research u u Streaming Techniques to minimize channel change time. u u Predicting next channel Regional Cache... When they're awake.
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Home Network n 100 Mbps Believed Sufficient u Several HDTV streams u Several Mbps left over for data n Options u 100 Mbps Ethernet u 802.11n or 802.11ac n May not be enough in a few years
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Worst Case Household Video Demand Source: "Future Fiber to the Home Bandwidth…", IEEE Communications Magazine, November 2012
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HDTV Video On Demand n Roughly 80 TV's per 100 U.S. Population n Current population about 322,400,000 n About 257.9 million TV's n Worst Case Traffic Demand 257,900,000 x 9.66 Mbps/user = 2,492,000,000,000,000 bps u All aren't HDTV capable u All won't be on u Should be some multicasting u etc.
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Video On Demand- Reservations I want to watch "Dr. Strangelove"Dr. Strangelove at 7:12 pm. Someone else in vicinity commenced watching at 6:58 pm? Reservations 1 hour in advance required? System can plan ahead. 6:58 request could be streamed live and forwarded (multicast) to my location, stored locally, played back commencing at 7:12.
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Unicast Server Router Sink 3 Separate Streams Required to service 3 users.
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Multicast Server Router Sink For a portion of the route, 1 stream suffices.
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