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The entertainment industry is undergoing a dramatic transformation. The delivery of video over IP broadband networks is now a reality, opening many new opportunities for service providers. A changing regulatory landscape, new technologies and delivery models, and the promise of ubiquitous broadband access have sparked new business opportunities among media and telecommunications organizations.
As traditional voice and Internet service providers consider offering TV and integrated video services over broadband infrastructures, current �TV providers,� such as cable multiservice operators, are also looking to the Internet as another distribution channel and as a means to expand the types of services they can offer. The technology for delivering television and value-added video services using Internet Protocol is called video/IPTV.
While very promising for many service providers worldwide, video/IPTV comes with challenges, such as scalability, operational complexities, and high quality of experience requirements, all of which can result in an inability to translate this promising opportunity into profit.
With technology, change often comes quickly. But, in the case of video/IPTV entertainment services, the pace of evolution has been particularly swift and has introduced unique challenges. Today�s video/TV market is characterized by:
Growing competition � Competition among cable and satellite TV organizations is already fierce and operators are increasingly challenged to differentiate their services, maintain customer loyalty, and reduce turnover. As traditional voice and non-traditional video content providers enter the market, competition is only increasing.
Profitability challenges � To enhance profitability while remaining competitive, service providers are searching for new ways to grow revenue and retain customers. They are also searching for new strategies to reduce capital expenditures and operating expenses.
An evolving market � Opening regulations in North America and elsewhere will soon allow a new wave of players to enter the TV market, led by traditional telephone and Internet service providers. Concurrently, consumer adoption of broadband Internet is reaching unprecedented levels. According to IDC, there were 146 million broadband subscribers worldwide in 2004, with 317 million expected by 2009 � a compounded annual growth rate of nearly 17 percent.
New technologies that enable scalable video over IP � A wave of emerging technologies (including advances in video compression, IP Multicast, QoS assurance, and DSL speeds) will enhance existing video networks and dramatically expand the capabilities of networks that today primarily support voice and broadband Internet services.
Service convergence � More and more, consumers are bringing a �triple play� of voice, video, and broadband Internet access onto their home computers or televisions. Major operators are already moving to deliver all these services as a �bundled� product offering that will allow for new capabilities, cost savings, and revenue models. In the near future, this convergence will also extend to other multiservice devices in the networked home, as well as to mobile devices and networks, enabling �triple play on the move.�
Evolving business models � Changes in both the consumer TV/video market and transport network technologies are reshaping the TV landscape. The types of content, the ways in which content is viewed, the methods of broadcasting, and the level of interactivity between viewer and content are all undergoing dramatic transformations. (Refer to Figure 1.)
Those service providers willing to embrace emerging technologies and adapt their business models to the new market realities stand the best chance of succeeding. But, establishing and maintaining a successful market position over the next decade will require more than just a willingness to change. Service providers also need an intelligent, flexible, and reliable technology infrastructure that is capable of supporting emerging �triple play on the move� services, as well as delivering current services more efficiently.
Increasingly, service providers are recognizing that IP is the ideal foundation for scalable, resilient, cost-effective video networks. With a robust, intelligent IP network, operators can efficiently deliver true triple play services with mobility and position themselves to make the most of this unique and growing market opportunity.
Deploying IPTV is a significant undertaking. In many ways, it�s more challenging than implementing voice and data because it requires sometimes complex interactions between a range of systems (e.g., digital rights and asset management, video head-end encoding, ad insertion, set-top boxes, and the IP network). A successful implementation calls for a balanced systems approach that puts functionality in the right place � from the head-end through the network to the set-top box � making the right linkages among those architectural elements, so that the system can scale cost-effectively and deliver a quality user experience. Successfully navigating the complexity of deploying IPTV requires the seasoned know-how and experience of partners that have deployed large-scale video networks previously.
Scalability
The true challenges of deploying an IPTV service are exposed as the service provider must support a growing number of subscribers.
Scalability demands vary with the type of IPTV service. For instance, when scaling the network to support broadcast video services, service providers need to factor in support for national and local standard definition (SD) and high definition (HD) channels, inter-region channels, ethnic programming, and local ad insertion. Furthermore, market pressures will push them to increase the number of offered channels and to add more HD channels (which will likely also need to be simulcast in SD). Supporting these video streams will consume lots of bandwidth.
National streams may enter the network through a super head-end centrally located in the country and local channels via video head-ends in each metro area. Moreover, some programming may be broadcast to some neighborhoods and not others in order to best meet demographic demands. Therefore, inflexible Layer 2 schemes that blindly deliver all channels to all parts of the network will be expensive from both a capital expenditure and an operating expense perspective.
What�s needed is a Layer 3 dynamic multicast capability to provide an efficient way to deliver broadcast channels only to the parts of the network that actually need them. This is especially important for carriers that have to lease their transport capacity. In addition, a dynamic multicast capability can support multiple injection points (the places where channels enter the network) and change channel lineups with greater operational ease.
Too often, the impact of a video on demand (VOD) services on scaling the network is underestimated. Successful providers of VOD are seeing peak demands that exceed 10 percent of their digital video subscribers using the VOD services at the same time. Since each VOD user requires a separate video stream through the network � as opposed to a broadcast channel, in which a single stream serves many subscribers � the bandwidth demands of VOD traffic can far exceed those of broadcast video. Network designs need to cost-effectively account for this.
Since video takes up so much bandwidth, compared to voice or data services, it often becomes the foundation for a converged network infrastructure. When designing a converged network infrastructure it is imperative to cost-effectively address the diverse bandwidth, reliability, and routing requirements of the converged service set (voice, video, and data).
Quality of Experience
Video subscribers expect a high quality picture. As a rule of thumb, there should be no more than one dropped packet per two-hour movie (a dropped packet can translate into a disrupted video picture, often described as macro-blocking). Such a stringent packet loss rate far exceeds the network demands of any voice or data service. The underlying network infrastructure needs to have the QoS mechanisms to ensure a high quality video picture. Sometimes the mechanisms used for voice and data services aren�t sufficient.
For example, monitoring video packet loss rates with the techniques previously used for monitoring voice and data packet loss rates is often not effective because the video requirement is orders of magnitude lower and therefore may not be detectable with those older approaches; new techniques and innovations are required.
Another example is the need for video admission control. In today�s world, metro voice and data networks are oversubscribed. Service providers count on the variability of the subscribers� usage of their services and cost-effectively size their networks using economies of scale. If more data traffic is offered to the metro network than it can handle, the network will start dropping packets and slower Web access results.
As service providers offer IPTV services, economics will again push them to oversubscribe their metro networks. If more video traffic is offered to the metro network than it can handle, and the network starts dropping packets, the result isn�t slower video service. Rather, it�s poor video picture quality, because dropped packets appear as macro-blocking on the TV. Furthermore, the video picture quality of an entire neighborhood could be adversely affected.
In response, service providers need to implement a video admission control scheme to prevent the acceptance of video streams that would push the metro network over its capacity. This requires two things. First, the video application must be linked to the network. Although the application recognizes the request for a video stream and knows where it will originate, the application needs to be tied to the network�s knowledge of bandwidth availability along the path the video stream is following � from the source to the set-top box. Second, service providers need to take an approach that can deal with the complex topologies of the metro network.
Of course, it is impossible to maintain high-quality service if system availability is at risk. Therefore, an IP-based network transporting video traffic must be configured with redundant components and multiple connections throughout the network to ensure uninterrupted service in the event of a failure. Because service providers place a higher level of availability on broadcast services than on VOD, some service providers are deploying redundant video head-ends. As a result, if one head-end fails, the network should be able to automatically switch to the other, ensuring an almost imperceptible interruption of service.
Requirements for IP next-generation video networks
To succeed in tomorrow�s video market, service providers must be able to deliver:
� On-demand interactivity, including interactive guides and services, VOD with network-based personal video recorders (PVRs), and support for home-based PVRs;
� Rich content variety, including more specialized channels and local channels, as well as more HD content;
� Superior customer experience, encompassing both high quality video and audio and maximum service reliability;
� Expanded accessibility, so that customers can receive and interact with services through a variety of access technologies and devices;
� Integration with the networked home, allowing a convergence of multiple services and devices;
� The ability to interact with mobile devices and wireless networks, allowing TV and video content to roam with customers just as easily as voice communications do today.
As many providers are discovering, the most effective way to meet these demands is to provision and manage all consumer services � TV, voice, and broadband Internet � over a single, converged, intelligent IP network that offers innovative, cost-effective, and scalable approaches to IPTV delivery, regardless of the provider�s choice of access technology (i.e., cable, DSL, Ethernet, or fiber). These next-generation IP networks can help service providers deliver scalable video more flexibly, reliably, and cost-effectively, while providing a richer, higher-quality customer experience. IT
Paul Sanchirico is Senior Director, video/IPTV Network Systems Group, Cisco Systems (News - Alert), Inc. For more information, please visit to company online at www.cisco.com.
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