Definition of IPTV
What is IPTV? This is a fundamental issue.
Before the introduction of the definition of IPTV by the International Telecommunication Union, different standardization organizations and related enterprises had various interpretations of IPTV, and in China, IPTV was also translated into various forms - interactive television, online television, interactive television
At the same time, different industries, operators, and equipment manufacturers have different opinions on what IPTV can do. Although the prospects of IPTV have been described as a huge cake, how to slice the cake has become the focus of industry attention, and all parties are doing their best to seize the opportunity in this huge market.
In fact, due to unclear policies leading to unclear industrial models, behind the popularity of China's IPTV industry, more people are cautiously watching; The limitations of bandwidth and content, as well as the barriers to unified terminal standards, have led to the inability to promote IPTV on a large scale, many experiences cannot be summarized, manufacturers are at a loss, and marketing has also fallen into the awkward situation of thunder, rain, and little. Therefore, the introduction of IPTV international standards will to some extent change the awkward situation of unclear identity, uncertain standards, and feudal separatism.
In the IPTV standards published by the International Telecommunication Union, the definition of IPTV is as follows:
IPTV is a multimedia service, such as television, video, audio, text, images, data, etc., and has certain QoS/QoE, security IPTV is defined as multimedia services such as television/video/audio/text/graphics/data delivered over IP based networks managed to support the required level of QoS/QoE, security, interactivity, and reliability.
From the definition of IPTV by the International Telecommunication Union, we can see that it mainly includes the following meanings:
IPTV is a multimedia service, and services such as television, video, audio, text, image, and data are all manifestations of IPTV;
IPTV is carried on a manageable IP network and has corresponding level requirements for security, reliability, interactivity, and service quality.
IPTV is not so much a business as a service. Although it may seem like a different translation of a word, it means looking at IPTV from different perspectives, and "business" is more from within the operator, which is the business project used by the operator to earn profits; However, "service" is defined from the perspective of customers, that is, IPTV can meet the needs of different categories of customers. Therefore, the author prefers to interpret IPTV as a service to customers rather than an internal business of the operator.
Through this definition, we can find that concepts such as online television and interactive television are only a description of IPTV's image and cannot fully cover the meaning of IPTV. However, this definition still has certain positive significance for promoting IPTV and promoting its development in China.
IPTV service requirements
In the IPTV standard, the service requirements of IPTV are subdivided and listed according to service direction, function, etc. Some are required, some are recommended, and some are optional. This is actually a law that has been explored based on summarizing the development experience of IPTV around the world.
In the early stages of IPTV development, people wanted to incorporate all the functions that the Internet could provide, not only to achieve video on demand, video live streaming, online browsing, but also to achieve applications such as videophone or conference television, pursuing "large and comprehensive". However, this is not realistic, as the result often makes the devices and systems too complex and the network overwhelmed. Therefore, it is not only necessary but also necessary to classify IPTV services appropriately.
In short, IPTV is a new industry formed by the intersection of multiple traditional industries, including operators, equipment manufacturers, content providers, terminal manufacturers, and other links. The coordination and integration of the industry chain is the determining factor for its market success; The value chain of IPTV is more complex, involving multiple types of enterprises such as set-top boxes, CDNs, DRMs, middleware, audio and video codecs, etc. The complexity of the IPTV system and architecture can be seen from its standard documentation.
1、 Service requirements required
Support content of different resolutions, including high-definition (HD) and standard definition (SD) standard TV programs;
Support different display ratios, such as 4:3, 16:9, etc;
At least one method is supported to avoid sending content that cannot be displayed to IPTV terminals (such as set-top boxes);
Capable of measuring service quality for key parts and points;
Can define key services and their interfaces with other domains;
Allow two-way communication between end users and service providers;
Support addressable specific devices, such as IPTV terminals in user networks;
Allow the use of internet protocols and standards. recommend
Support content segmentation;
There is a mechanism for obtaining relevant terminal device functions;
There are corresponding functional blocks that can provide open interfaces for third-party applications to use IPTV network functions and resources;
Ensure the integrity of content and segmented data;
Support online personal video recording;
Support the display of multiple video streams;
Allow IPTV services to be sent over different networks (such as cable television networks, fiber optic networks, xDSL, wireless networks, etc.);
Allow IPTV services to run on different IPTV terminal devices (such as mobile phones, PDAs, set-top boxes, etc.);
When sent through a mobile network, the IPTV architecture should be able to dynamically adapt to changes in wireless network parameters (such as bandwidth, packet loss rate, etc.);
Support tracking and investigation of ratings and other data;
(Note: This tracking survey may allow content providers and service providers to publish audience rating services, track data of popular programs, or push specific advertisements for users with certain surfing preferences)
You can upgrade software versions and download system configuration data by connecting to the download server;
Support the use of XML encoding for application signaling;
Only specific users can be allowed to view certain content, and this authorization can be triggered by service providers or users;
The manifestation can vary depending on the usage environment;
Terminal devices should be able to explain the actual usage environment, such as service type, terminal type, transmission medium type, user interface, available service level
Optional
Support the storage and distribution of individual fragments or entire media content;
Alternative methods supporting content caching and distribution;
Can be interspersed with advertisements;
Support time shift TV function (playback of played content);
Support a description of the usage environment. Terminal device options
Support the change of display time;
Require support for at least one audio and video decoding format;
Ensure correct time synchronization control, such as being able to maintain consistency between the sound and video mouth shape no matter when the audience pauses, replays, or randomly accesses at any time;
Support the recording of data files or playback of audio and video content on the network or IPTV terminal devices;
Within the authority of the digital broadcasting network, seamless switching of encoding and decoding technology is supported, such as the ability to schedule daily switching between high-definition and standard definition content.
（1） Settlement and billing required
Support various payment methods for IPTV service fees (such as prepayment, use before payment, notification payment, third-party payment, etc.);
All IPTV services can use NGN's billing architecture for settlement and accounting functions;
IPTV needs to have a data and historical information collection mechanism for financial settlement and reporting purposes, partner settlement, and end-user reconciliation, such as subscription, purchase, and transaction records of services;
Support other billing and settlement methods related to IPTV services.
recommend
Allow service providers to integrate the settlement and billing functions of IPTV services into multiple NGN services and applications;
Settlement information can be transmitted between service providers.
1. Subscription
Support the registration function of users.
2. Pay per visit
To purchase appropriate VOD content to fulfill the licensing agreement.
3. Income system required
There is a mechanism to support PPV (Pay Per View) services;
To support On Demand services;
Consider the need to insert other content into VOD content;
Support interactive services such as educational and entertainment applications (such as games), communication services (such as email, chat, and SMS), and information services (such as stock and weather forecasting services);
Support the distribution of interactive and downloadable games;
Support the search, download, storage, and display of digital photos;
As long as there is a regulatory need, corresponding content can be sent to specific regions;
Allow service signaling to be routed based on the capacity of end users' devices or application servers;
Consider the manageability of service transmission quality across multiple domains;
Support Network Address Translation.
recommend
Support the integration of IPTV services with existing services (such as instant messaging, telephone);
Allow seamless provision and operation of IPTV services within different management domains;
If it supports the retransmission of radio programs, it is recommended to support geographical differentiation of content;
Support remote configuration and management of network and service elements;
Can receive content from different sources, such as satellites, IP private networks, etc;
There is an information exchange mechanism that can obtain profile information of users who meet certain conditions (such as ID information in digital rights management);
Support the establishment of conversation pathways that maintain relationships between users and their applications.
Optional
Content can be locked or restricted based on user profiles and usage preferences;
Can convert video content from its original storage format to a compatible format that IPTV terminal devices can display;
Allow users to become content providers in order to share their content;
Service providers can block and prevent a large amount of unsolicited content from being sent to end users;
The source of the content can be traced (if the content has caused complaints or complaints from end users).
（2） Subdivision by Role
1. Content provider
Support content providers to manage content, such as uploading, deleting, or modifying related attributes of content;
Allow content providers to collect usage information on content.
2. Service provider required
Allow service providers to operate, manage, maintain, and provide (OAMP). IPTV equipment;
Service providers can easily manage IPTV service failures, configurations, settlements, performance, and security (FCAPS);
Monitor network equipment (such as routers) and service equipment (such as IPTV terminals), and alarm in case of failure;
The service content can be integrated and displayed through IPTV devices, and can be sent through non IP or IP methods;
Allow IPTV services to be distributed through agreed third-party providers;
Electronic navigation function supporting IPTV content
Service providers can verify user information, authorize users, and charge subscribers;
Support service providers to verify the permissions of end users to purchase products, order VODs, or watch restricted programs, such as using PIN codes or login methods;
Service providers need to be able to distinguish between end users and subscribers.
recommend
If the retransmission of broadcasting services is supported, it is recommended to provide the same QoE (user experience) as the direct receiving user;
Service providers can operate various types of services;
The service provider has subscription management functions, such as opening, canceling, activating, or freezing accounts, checking user account balances, searching for detailed consumption records, correcting user information (such as account name, login name, payment method, etc.), and dividing whether it is a group user;
Service providers should ensure normal service while also preventing misuse of services;
P2P mechanism can be recommended in IPTV, but it does not exclude the use of CS (client server) mechanism.
Remote management requirements
Service providers should be able to remotely upgrade end users' devices;
Support service providers to obtain QoS (Quality of Service) information from terminal devices;
The service provider should have access to the functions of the user's IPTV terminal device (such as codecs, access restrictions, etc.);
Recommend service providers to remotely upgrade terminal devices, such as upgrading software, drivers, and updating virus libraries.
Content push requirements
Support service providers to push content to end users' IPTV terminal devices (content can be requested by users or not);
Service providers can insert additional content into users' PVR content playback.
3. Network provider
If wireless broadcast retransmission is supported, it is necessary to ensure that network providers protect the privacy of end users like broadcast networks.
4. End users
essential
Can filter out unwanted content;
Allow end users to switch between free (FTA) and pay per view (PPV) environments;
Users can choose their own settings (including audio, dialogue, subtitles, additional videos, and explanatory audio) from multiple language versions of the content;
Users can turn on or off audio, dialogue, subtitles, and additional audio and video at any time without changing the preset options;
Users can store and retrieve configuration files for their preferred settings and language settings, so that different users can switch between different configuration files.
recommend
Support subscribers to query a detailed list of usage records.
Optional
Content providers can set language options for their own content.
（3） Association with other service networks is required
IPTV terminal equipment should continuously monitor EAN (Emergency Alarm Notification) information;
To manage all IPTV subscribers, it is not ruled out to use HSS (primary user server), SLR (service level requirement), or NGN related functional components.
recommend
Support interoperability and user mobility between different IPTV networks, allowing users to access IPTV services regardless of whether they are mobile or not;
Allow network operators to comprehensively utilize their existing network capabilities;
Support service providers or network operators to integrate IPTV's subscriber management function into a subscriber management system, which can be applied to multiple NGN services, including IMS (IP Multimedia Subsystem) based services;
It is recommended to integrate IPTV services in an IMS based environment, which relies on the specific functions of IMS based NGN, including (but not limited to) HSS, SLR, and GUP.
Support real-time encoding and precoding of stored programs;
Support the exchange of IPTV service information between different IPTV service providers, such as sources, channels, service start and end times, and QoS information. (To be continued)