|Issue:||Europe II 2007|
|Topic:||The IPTV edge|
Reto Brader is the General Manager for Pixelmetrix Corporation, a Singapore-based company that specialises in the design and production of management and telemetry systems for digital broadcasters, satellite, cable and IPTV operators worldwide. Mr Brader has more than 12 years of digital data, video distribution and monitoring experience. Prior to joining Pixelmetrix, he was Product Marketing Manager at Hewlett-Packardís High-speed Telecom and Digital Video Test Division in Canada. Mr Brader currently represents Pixelmetrix in the DVB Forum. Mr Brader holds a bachelors degree in Electronic Engineering and a masters degree in Business and Administration (MBA).
IPTV, using the Internet protocol to deliver TV, is the best hope fixed-line telcos have to complete the triple-play – voice, data and video – package they need to compete with ISPs and cable companies. Moving to IPTV is not simple; there are many challenges, from programming to technology, that they must master. Only constant monitoring of everything from the content delivery to the technical parameters – a demanding task – will guarantee the sort of experience and end-to-end quality users demand.
IPTVís ignition is on. The spark of this emerging technology stirred much hype among the telcos and cable operators as they look to harness this technology for their content delivery infrastructure. Dwindling wire line revenues, increased competition, bundling opportunities, consumer demand for greater control over viewing preferences, falling voice revenues, increasing penetration of broadband ñ telcos all over the world have finally realised the importance of shifting from a voice-centric model to an IP-centric model in which video and other content-rich interactive services play key roles. IP networks enable telecommunications operators to provide their customers with IP-based television, IPTV, as well as myriad next-generation IP-based services that end users incorporate into their increasingly digital lifestyle. It is indeed the network operatorís strategy for tomorrow. IPTV excites! What does it offer? With IPTV, telco operators can implement all the traditional services available on rival technologies – e.g. satellite – such as: ï free-to-air broadcast channels; ï premium broadcast channels; ï radio channels. Thanks to the high-speed connection and the always-on ëreturn channelí, telcos are also able to implement interactive services such as: ï T-Mail, which allows customers to access their email accounts on television; ï T-Browsing, which allows customers to surf the Web on TV; ï T-Services, which enable shopping or banking services on TV; ï T-SMS and T-MMS, television-based short message and multimedia message services; ï network PVR, personal video recorder, and network Time-Shift Television, TST; ï viewer voting and polling. Multimedia Research Group estimates that IPTV subscribers will balloon from eight million in 2006 to 50.7 million in 2010 (worldwide), with Europe leading the market. The industryís revenue could reach nearly US$13 billion by that time. IPTV is growing in leaps and bounds. Whatís the big challenge? IPTV has huge market potential, rich interactive services and gives choice to customers. IP television, while alluring, also carries many big challenges for telcos; in fact, to make a mark in this market successfully, they have to focus on efficient business and operating models, regulatory issues and enhancing their technological capabilities. All these factors collectively play an important role in defining the experience of their customers. One of the prime challenges faced by IPTV service providers is the customerís expectation of ëalways oní service. The constant availability of all IPTV programmes and services is a critical factor for the success of a service. Cable and satellite providers have set the bar extremely high in terms of the richness of content offering, availability, quality and pricing of television services. This leaves IPTV service providers with multiple challenges – challenges that every service provider must overcome to achieve successful service roll out. Correctly addressing the above factors requires careful network design. Comprehensive systems for managing the customerís quality of experience are a key component of that strategy – to guard against known challenges and staying prepared for the unknown. Quality of experience To harness the power of IP and digital television fully calls for the reconciliation of these technologies designed for ëbest effortí and real-time delivery of content respectively. The immediate goal, however, is to provide user-centric IP services in line with customersí demand for total end-to-end QoE, Quality of Experience. The success of IPTV lies in the adoption of best practices in service planning, deploying, managing and maintaining the service. Quality assurance covers the complete network, from signal acquisition to end-user delivery. In order to implement quality assurance, priorities must first be defined. This can be achieved by studying error impact: if a DSL, digital subscriber line, is not functioning properly – dropping packets, for example – video quality will be compromised. The acquisition of live content in the IPTV head-end must be monitored. If a stream fails to leave the head-end, customers will be affected, disrupting their viewing pleasure. Monitoring success The many technical challenges make a strong case for the use of extensive test and monitoring in both the deployment and the operation of an IPTV network. The end-to-end monitoring of IP networks, from checking the integrity of content at ingest to the intended delivery to the final customer, is a must. A key strength of IPTV is the wealth of monitoring and control information that can be collected, aggregated and correlated to determine video and audio quality on a network-wide and per-user basis. Taking QoE measurements from all elements in the service delivery path makes it possible to correlate transport-layer QoS with application QoE. Therefore, network transport errors can be compensated at the application layer through the use of error correction algorithms or packet retransmission. The IPTV network needs to be monitored geographically, across different locations and identified monitoring points within the network, and over time, since historical performance data is as important as todayís real-time telemetry. Also, monitoring should include problems in the transmission chain as they happen, now, and for problems that might be expected to manifest themselves over a period of time. Also, most importantly, monitoring of the protocol axis is essential to insure the integrity of the signal is maintained and that the content is reaching the subscriber. Maintaining service integrity is a major issue; this means guaranteeing that the right content – the content the subscriber expects – is delivered. To elaborate on the importance of monitoring each aspect of the IPTV delivery chain at identified monitoring points, let us consider the head-end. IPTV head-end designers can tap on the experience of well-informed head-end operators with regard to what they consider a key problem – loss of the incoming signal or part of it. Another common issue that arises is when ësomething goes wrongí within the decoding and encoding chain; this leads either to erroneous or no output from the head-end. Accordingly, the monitoring solution must actually ëlook and listen, to determine that there is content within the IP packets. If there is no signal from the input, most of the equipment in the transmission chain will produce a pre-defined output; this could be anything from a black screen, to a test signal without audio, to a simple test tone. The only way to ensure that ërealí content leaves the head-end is to check the content continuously at a number of control points. If an error is detected, operators need the tools to check that the input is in order and to identify the causes of the errors. Information at each layer of the protocol stack is equally important to determine what sort of ëcontent experienceí the customer would get. Monitoring solutions are designed with a clear focus on the lower layers of the protocol stack for bit, byte, datagram, packet and transport stream, etc, errors. The questions, among others, that need to be answered are: Are the subtitles on the content right? Is the content audio good? Does the parental control work as intended? Is the channel changing on time? The experience is decided by factors that cannot be confined to a single protocol layer or a group of layers, but correct data and processing at every single layer has an equal contribution towards delivering quality experience. IPTV networks cover large areas. The service provider needs to have complete visibility of the service throughout the area to ensure an end-to-end quality experience. The monitoring system should consolidate all the telemetry data at a single point, so that the system as a whole can be audited by the network owners and provide complete data for all parties with a stake in the successful delivery of content, from content aggregators, content owners and network equipment manufacturers to IPTV systems vendors. IP television is here to stay. The Internet protocol is redefining the way we perceive and consume video content. It empowers consumers to decide what they want, how they want it, where they want it and how much they want. The adoption of this path-breaking technology brings challenges, but they can be faced head-on; there are efficient strategies to overcome them. Customer-centric business models, robust technologies and, most importantly, continually delighting the customer with exceptional quality experiences, are important elements of a successful IPTV service. Customer churn, and the drag it has on revenues, can be reduced by using efficient test and monitoring platforms. These ensure that problems are attacked before they affect the viewer. The three-dimensional protocol model for efficient monitoring takes into account all the significant aspects of IPTV network monitoring: the geography; time; and, protocol stack. IPTV is more than about meeting requirements; it is about surpassing expectations.