Wi-Fi 802.11n Based Access Network for IPTV Service Delivery in Pakistan
Wi-Fi 802.11n Based AccessNetwork for IPTV ServiceDelivery in Pakistan Fahad AhmedStudent of Master of Telecommunications Engineering University of Melbourne Jawad-ul-Hassan SiddiquiStudent of M.Engg Communication Systems & Networks Mehran University of Engineering & Technology
Traditional CATV Standard Composite TV signal has a bandwidth of 6 MHz Vestigial side band Amplitude modulation is used for video signals and FM is used for Audio. Various channels are broadcasted together having different carrier frequencies( using different carrier frequencies for Composite TV signal of each TV channel) by using FDM. There can be only 135 channels broadcasted in a traditional CATV system due to bandwidth limitation i.e 54Mhz to 890 Mhz enforced by PTA.
What is IPTV ? IPTV is a new form of Cable TV and provides more features then Cable TV In IPTV a real time TV broadcast is encoded by using MPEG2 or H.264 Codec, the encoded real time video streams encapsulated into IP packets and multicast over the IP network having end to end QoS control.
Customers Expectations Subscribers want noise free, clear high quality picture quality TV channel broadcast. They also want access to more TV channels. Subscriber want to watch the contents of their own choice , when ever they want. Subscriber want more personalized viewing and interactivity in their daily life viewing. Subscriber want to view the contents whenever they are free or want to watch recorded real time video streams. Advertisers want to increase their advertisement viewers and want to target the viewers who seriously think about their product.
Subscribers want noise free, clear highquality picture quality TV channelbroadcast. IPTV provides noise free, high quality picture. In IPTV, the Live TV video contents are received from the TV channel broadcasters via satellites or other terrestrials links, video contents are then encoded and compressed by the codec like H.264 or MPEG2, the encoded video contents are distributed via IP-multicast delivery.
Subscriber want to watch the contents of their own choice , when ever they want. IPTV provides Video on demand ,VoD provides solution to this requirement, VoD allow users to search their desired multimedia contents from online videos/movies libraries, when a user makes a selection, the video streaming server start delivering the multimedia contents to the user over a point to point unicast connection. VoD also provides VCR like functionalities known as trick mode.
Subscriber want more personalizedviewing and interactivity in their daily lifeviewing. IPTV provides interactive TV viewing allowing viewers to interact with the multimedia contents, because its an IP based content it is very easy to provide along with video contents and provides a two way communication path which enable user to send their data also. Interactive TV has various features like Electronic Service/Program Guide, Personalized viewing, different viewing angles, users can participate in online polling, multimedia content searching system allow user to search for contents based on actors, title, release dates, director etc
Subscriber want to view the contentswhenever they are free or want to watchrecorded real time video streams. IPTV provides the solution in two ways i.e personal video recording allow user to record multiple broadcast (IP-Multicast) streams on their PVR therefore user can access recorded content whenever they want. Other method is Network based PVR, the real-time TV broadcast is recorded on a server at the service provider network therefore the subscriber can access the contents whenever he/she wants from that server.
Advertisers want to increase their advertisementviewers and want to target the viewers whoseriously think about their product. IPTV provides an interactive solution in the form of addressable advertisement, in this feature the advertisers search the profiles of the viewers and selects the profiles which are best match for their campaign/advertisement and sends an interactive advertisement to the particular viewers.
Smartness of IPTV Since it is an IP based data cast it is easy to be provided over broadband internet connection Special end to end QoS(quality of service) provide defense against network jitter, packet loss and long transmission delay faced by the multimedia content in internet. IP multicasts of real time video streams, in which few requested streams are delivered to the subscribers (who request the streams) enable service providers to provide cable TV like environment and increases the number of choices for the users to choose from thousands of TV channels and also make it possible to provide HDTV.
Smartness of IPTV Whereas in old cable TV or in digital cable TV all of the channels are broadcasted therefore they consumes large bandwidth and a user is tuned to a particular channel whereas all other channels which are not being watched by the user are also being broadcasted and consuming the remaining bandwidth, this bandwidth consumption creates a problem in providing large number of channels and in providing HDTV channels on a old analog cable tv or on a digital cable TV.
Smartness of IPTV In IPTV different services like Voice, Data and video services are IP-based therefore they are easy to converge and provides new way of interactivity and converged communications. An user can enjoy features like on screen caller ID, on screen call handling, video calling, chatting, voice mail and e-mail handling, information sharing etc and parallely he/she can watch video.
Attraction Of IPTV Less bandwidth consumption of IPTV and be a IP-Data encourages the Telco to provide IPTV in bundle with Internet Access and Voice services (e.g VoIP) over broadband connection.
Hindrances in IPTV Service Delivery All ready laid networks are designed for data traffic, so the routine problems are quite evident like loss of packets due to circumstances like congestion delay, link failure etc. These problems are not a major point of concern in data networks because we mostly have retransmission facility at our disposal in case of packet loss or delay.
Hindrances in IPTV Service Delivery But IP based video data is greatly affected by such problems and requires a good quality of service mechanism, therefore it requires sufficient amount of bandwidth for video services to prevent bursty delivery of video data to the IPTV client equipment which is expecting constant data in correct sequence. The theoretical maximum downlink data rate of ADSL2 is 12 MBits/sec, if we consider ideally the data rate available to every customer averagely 10 Mbits/sec, therefore it is still difficult to deliver HDTV( High Definition TV channel require at least 6.5 to 8 Mbit/sec if they are using H.264) along with the multiple e.g 4 or 5 streams of SDTV(Standard Definition TV channel require at least 1.5 to 3 Mbits/sec if they are using H.264) and other services like VoD, High Speed Internet.
IPTV in PakistanIn Pakistan only one Telco which is providing the facilityof IPTV over their PSTN copper lines by using ADSL+technology.Unfortunately in Pakistan, the condition of most buriedPSTN copper lines to the customers are in worstpossible condition due to improper shielding of wires,copper wires buried in areas having water loggingand salinity, unmanaged planning and distribution, allthese factors cause failure and increases the noiseand causes an unreliable service delivery to thecustomer due to increase in packet loss.
IPTV in Pakistan Therefore the data required for good quality of service is greatly influenced by the factors discussed in the previous slide. Also an another issue is that data rate available to the subscriber vary according to the distance from the DSLAM (digital access line multiplexer) therefore some may get higher data rate who are closer to the DSLAM and some may get lower data rate who are far from the DSLAM.
What is the REMEDYThere can be many solution for thisproblem such as use of FTTH( Fiber tothe house) as an access technology,which provides a high bandwidth butmostly immune to the factors discussedpreviously and moreover thistechnology requires new infrastructurewhich is again expensive.
Proposed Solution Another solution to this problem is “Wi-Fi Technology” for access networks. Service provider can use fiber to node and after that use Wi-Fi 802.11n as a last mile access network. Wi-Fi alliance has announced a new standard for Wi-Fi i.e 802.11n which provides 4 to 5 times higher data rate as compare to 802.11 a/b/g/e.
Advantages of Wi-Fi 802.11n The renewed standard uses 52 subcarriers where as its predecessors uses 48. It has a FEC( forward error correction ) of 5/6 whereas the old one has 3/4. It has 400 nsec guard interval between transmission whereas 802.11 a/b/g has 800 n/sec. It has it has a channel bandwidth of 40 MHz where as 802.11 a/b/g has 20 Mhz.
Advantages of Wi-Fi 802.11n Wi-Fi 802.11n is greatly optimized for audio and video traffic, it has feature known as WMM (Wi-Fi multimedia) which provides QoS functionality by prioritizing the video and audio traffic. The higher throughput, QoS and reliable service delivery made this technology to be used as an access network for IPTV.
This is the future IPTV service provider can provide all the features VoD, interactive TV, High speed internet Access, VOIP and multiple SDTV and HDTV channel streams to their customers. Using Wi-Fi 802.11n technology provides the solution to the problem faced in copper networks of Pakistan. Wi-Fi provides an easy way to provide multiple connections to a same home if they are using more than one set-top boxes.
This is the future Higher data rates of WiFi 802.11n enable service provider to send several IP multicasts of SDTV and HDTV streams (which can be viewed on several TV or recorded simultaneously on PVR) along with multiple streams of high definition VoD( Video on Demand), High speed Internet Access and multiple VoIP services on a single connection to a subscriber.
This is the future Wi-Fi 802.11n WMM QoS provides solution to the problems like jitter, packet loss and transmission delay faced by the audio and video streams. Wi-Fi 802.11n also provides mobile convergence facility.
This is the future Wi-Fi 802.11n provides Mobile phone convergence, therefore a Wi-Fi compatible mobile phone or other handheld devices can use Wi-Fi access network for making VOIP calls, receiving IPTV services on Mobile Phone and use it for high speed internet surfing. Service provider also attract lots of mobile phone subscriber through Wi-Fi Mobile Convergence(WMC) feature
ConclusionUsing Wi-Fi 802.11n as an access network for IPTVservice delivery in Pakistan provide solution for theproblems faced in copper based access network andhigh bandwidth availability with Wi-FiMultiMedia(WMM) QoS provide high quality ofservice delivery to the subscriber along with all thefeatures of IPTV and bundle services like Internetand VoIP.Wi-Fi 802.11n has MIMO antenna technology whichprovide robustness in Wireless environmentattenuation factors and multipath problems.
ConclusionIts high time for the service providers to think alongthese lines and use the latest and probably the mostfeasible technology, to provide better IPTV service.Wi-Fi 802.11n also helps service provider to deliver theirservice in rural areas of Pakistan because severalrural areas of Pakistan don’t have PSTN, in ruralareas usually the homes are spread over larger areastherefore usage of Wi-Fi technology is a goodsolution for providing internet, VOIP and IPTV servicein rural areas
References  IEC Online Education Web Pro Forum: IPTV http://www.iec.org/online/tutorials/iptv/index.html  IPTV Wikipedia http://en.wikipedia.org/wiki/IPTV  An Introduction to IPTV http://arstechnica.com/guides/other/iptv.ars/1  IPTV & Triple Play http://www.rogertowne.com/IPTV&TriplePlay.htm  Digital Broadcast TV http://www.iptvxl.com/applications-services/digital-broadcast-tv/  Video on Demand http://en.wikipedia.org/wiki/Video_on_demand
References  Interactive TV http://en.wikipedia.org/wiki/Interactive_television  Personal Video Recorder http://en.wikipedia.org/wiki/Digital_video_recorder  Pay-Per view http://en.wikipedia.org/wiki/Pay-per-view  Addressable Advertisement http://www.iptvxl.com/applications-services/addressable- advertising  White Paper: IPTV http://www.intellon.com/pdfs/IPTV_White_Paper.pdf
References  White Paper: Delivering converged entertainment and communication services with IPTV and VoIP Multimedia for regional carriers http://www.nortel.com/solutions/iptv/collateral/nn121420.pdf  IPTV Architecture http://www.iec.org/online/tutorials/iptv/topic02.html  IPTV Architecture & Technologies http://www.networkdictionary.com/networking/IPTV.php  Video on Demand http://www.iptvxl.com/advantages/vod/  A Guide to IPTV: The Technologies, the Challenges and How to Test IPTV http://www.tek.com/Measurement/App_Notes/25_20277/eng/25W_20 277_0.pdf?wt=520&rgn=ww&from=303271X314253&link=/Measurem ent/App_Notes/25_20277/eng/25W_20277_0.pdf