People are more informed and less deferential and more differential than ever before. They want, and demand, as much choice and control as possible over most aspects of their lives
People want control their own time and want to watch TV when it suits them.
IPTV operates on a different premise than traditional satellite or cable television in that only selected programming and on-demand content are delivered to the consumer. With Satellite and cable, all channels are being pushed all the time to the consumer's home rather than a per-selection basis. IPTV's ability to provide two-way communication (you request a program from the TV guide and the program is delivered to you) offers true interactivity for the customer with the environment. HDTV, movies, past TV shows, and all other content can be distributed on demand and service providers can tailor the requested content and advertising based on customer preference.
IPTV also offers such potential as on-demand video gaming and because it is using your broadband connection, it can interact with other Internet services such as Voice over IP (VoIP). Consumers may have caller ID displayed on their television. The potential is truly unlimited.
The broadband network has clear benefits over the older cable TV network.
With advancements in DSL throughput and video compression and most importantly, the ability to offer video services over existing DSL infrastructures IPTV takes the edge over traditional cable providers, delivering both broadcast-quality video and video on demand.
ADSL differs from other DSL technologies in that it provides an asymmetric distribution of bandwidth for one of the two routes within the interactive architecture. ADSL broadband is crucial to IPTV services since it allows interactivity, but is perhaps the preferred IPTV delivery technology because it allows the service provider more bandwidth for the delivery than it does for the user to interact. Initially, most analysts believe IPTV services will remain mostly a delivered medium with interactivity at a minimum. Video on Demand (VoD) and p2p delivery services would not require as much bandwidth as the download of content from the service provider's head end would. A more interactive architecture whereby the user sends as much data to the service provider as it receives would require a different DSL technology with equal bandwidth for both routes. Currently ADSL is popular in Europe and Asia.
The delivery of Internet protocol TV (IPTV) using DSL is an emerging and exciting technology that offers new business opportunities to service providers. ADSL2+ and VDSL2 data rates make it possible to easily integrate voice, video and data services over a single telephone line, commonly denominated triple-play services. With all these technological developments, it is now practical and economical to simultaneously provide multiple standard and high-definition television channels (SDTV and HDTV) to the residential user.
The term IPTV usually includes a broad range of programs or TV channels provided by one or multiple service providers. Additionally, it might include some specialized programming like concerts, special events and movies, provided only when requested by the user; i.e., video on demand (VoD).
Like every other evolving technology, there are multiple approaches for the delivery of IPTV across the core network and its transmission to the customer premises over an ADSL2+ connection. In general, video service providers first perform the coding and compression of the video signal typically using MPEG-2, MPEG-4 or WM9/VC-1 (it is at this stage that a trade-off between quality and required bandwidth occurs). Then, the video content is ready to be distributed by streaming IP packets using the user-datagram protocol (UDP), which is the preferred method of IP packet delivery when offering video due to its low latency. Once at its final destination, the subscriber’s house, the video stream is decoded by a set-top box (STB) and
played on the TV.
Cable television service providers, in an effort to boost their average revenue per user (ARPU), now offer competitive, high-speed data services in addition to another home and business staple MPEG-2 based digital video and high-definition television (HDTV).
Customers find a single source for both high-speed data and digital video services very attractive. And the telcos suffer because of it.
Of course, a very few xDSL customers enjoy one of the fastest and most cost-competitive Internet access services available—from 3 to 8 Mbps—which is easily capable of delivering the MPEG-2 bandwidth requirement of 2 Mbps for broadcast-quality digital video. But the short DSL loop length limits the total available market (TAM) at these speeds.
More DSL customers can get data rates as fast as cable at 1.5 Mbps, and, while this speed makes it possible to watch Internet streaming video based on the MPEG-4 Simple Profile (MPEG-4 SP) codec in real time, 1.5 Mbps is not adequate to deliver broadcast-quality MPEG-2 video streams. With a very limited TAM, the investments telcos require to deliver video over DSL is not easily justifiable using MPEG-2. Plus, two other market phenomena add to the telcos’ challenges and catalyze the need for new services that boost ARPU and grow market share.
ADSL2 is a technology that provides higher downstream rates of up to 12 Mbit/s for spans of less than 2.5 kilometers (8000 feet). ADSL2+, boosts these rates to up to 25 Mbit/s for spans of less than 1.5 kilometers (5000 feet).
Quality of IPTV
On any ADSL-based deployment, the quality of the consumer’s video is not just a function of the
network bandwidth (ADSL2+/ADSL) or the data stream, as there are a number of parameters that contribute to the customers’ perception of good vs.bad quality. As the video stream arrives to the settopbox and ultimately the television, it has gone through various protocol layers (e.g., physical ADSL layer, ATM layer, IP layer, transport layer,etc.). It is the interaction between these layers and the effect of external influences that affect the quality of the video perceived by the consumer; this is often referred to as quality of experience (QoE). Some of the parameters that influence the customer’s QoE include image pixelization and tiling, picture blurring and edge distortion, as well as audio dropouts and channel-change latency
(also known as zap time).
Packet Loss
Loss of IP packets may occur for multiple reasons — bandwidth limitations, network congestion, failed links, and transmission errors. Packet loss usually presents a bursty behavior, commonly related to periods of network congestion. Depending on the type of transport protocol used for the video streaming, a packet loss will have different impact on the quality of the perceived video. When UDP is used, the lost packets will directly affect the image, as the information cannot be recovered and the image will simply be corrupt or unavailable. When using TCP, a packet loss will generate a retransmission, which can produce a buffer underflow and, consequently, a possible frozen image.
Data rates for the downstream and upstream must be high enough to support IPTV. Even with MPEG-2 or MPEG-4 video compression, a speed of at least 3 Mb/s per channel is required in the downstream direction — and much more if HDTV is contemplated.
The new H.264/MPEG-4 AVC video coding standard enables telcos and ISPs to deliver high-quality video and television over digital subscriber lines (DSL), creating new revenue-generating opportunities.
Similar to MPEG-2, H.264/AVC requires encoding and decoding technology to prepare the video signal for transmission and then read it at the customer’s receiver (STB and TV/monitor, or PC). In fact, H.264/AVC can use transport technologies compatible with MPEG-2, simplifying an upgrade from MPEG-2 to H.264/AVC to help protect the investment in MPEG-2 some companies have already made, while enabling transport over TCP/IP and wireless. A significant difference, however, is that H.264/AVC does not require the expensive, often proprietary encoding and decoding hardware that MPEG-2 depends on, making it faster and easier to deploy H.264/AVC solutions using standards-based processing systems, servers, and STBs. This also allows service providers to deliver content to devices for which MPEG-2 cannot be used, such as PDA and digital cell phones. H.264/AVC is ideal for, but not limited to, Video Services over DSL; it increases the ground of applications based on a common video format.
H.264/AVC cuts in half the bandwidth required to deliver fullscreen DVD-quality digital video to consumers, and it reduces standard television quality digital transmission bandwidth requirements to 700 Kbps—both well within the capabilities of a 1.5 Mbps DSL loop. Using new H.264/AVC delivery platforms and standard PCs or STBs, telcos can offer exciting IP video services—video-on-demand (VOD), local, national, and premium television programming, gaming, music, and, even interactive television—to their home and business customers using their existing copper infrastructure.
IPTV advertising
With the promise of advanced capabilities offered by IPTV advertising, an important question becomes whether it can compete with the already-established online video ad industry. According to an industry report from research firm Understanding & Solutions Ltd., Internet TV advertising could achieve revenues of up to $10 billion worldwide by 2011, which equates to 18 percent of the total Internet advertising market for that year, which is forecast at $57 billion.
Despite the challenges, as new IPTV services continue to emerge, it’s only a matter of time before operators discover how to exploit the capabilities of interactive advertising on a wider scale, the same way as it has been done online.
