Nowadays, more and more often you can hear about such a service as interactive television or IPTV. What it is? IPTV is a system through which television services are provided using the Internet protocol suite over a packet-switched network (local or global), instead of data transmission using traditional terrestrial, satellite, and cable formats. Unlike downloadable standard media, interactive TV offers the possibility of streaming information in small sequential volumes, coming directly from the source. As a result, the user may start playback of data (such as a movie) before the entire file has been transferred. This is also known as streaming media.
Answering the question “IPTV - what is it?”, It should immediately be noted that it differs from Internet television, since its implementation is based on telecommunication networks with high-speed access channels, and data is transferred to end users using a set-top box or other client equipment.
IPTV - list of available services
IPTV services can be divided into three main subtypes:
- Live from the current TV broadcast.
- Listtime TV: Replays of TV shows that were broadcast hours or days ago, as well as replays of videos just watched.
- Video on Demand (VOD): Ability to browse the catalog of videos not related to the TV program.
IPTV – what is it: technology definition
Historically, there have been many different attempts to define IPTV. This technology is described as a collection of elementary or transport streams over IP networks, as well as a number of proprietary systems.
One of the official definitions approved by the International Telecommunication Union. According to it, IPTV is multimedia services (television/transmission of video/audio/text/graphics/other data via IPTV-player) received over IP-based networks. When implemented, it turns out to provide an appropriate level of service, security, reliability and interactivity.
According to another official source, IPTV is defined as the secure and reliable delivery of entertainment video and related services to subscribers. These may include, for example, video on demand (VOD) and interactive television (ITV). They are provided over a packet-switched network that uses the IP protocol to transport audio, video, and control signals. Unlike video over the World Wide Web, when IPTV is launched, it is possible to maintain greater network security and performance, resulting in an uninterruptedbroadcast.
How did this kind of TV develop?
The technology was initially hampered by low broadband penetration and the relatively high cost of installing electrical wiring capable of transporting IPTV content securely to customers' homes. Nevertheless, the use of IPTV is becoming more widespread today, and the number of subscribers continues to grow.
Elements
TV hardware is exactly the part where IP TV channels are encoded, encrypted and delivered as multicast streams.
The VOD platform is where video assets (IPTV playlist) available on demand reside. They are activated when the user makes a request as an IP unicast stream.
An interactive portal allows the user to navigate within various IPTV services (such as the VOD directory).
The supply network is a packet-switched network that contains IP packets (unicast and multicast).
Home TV Gateway - a piece of user equipment that controls the activation of the transmission of information or its deactivation.
Smart IPTV: A piece of user equipment that decodes and decodes TV and VOD content and displays it on the TV screen.
Video server network architecture
According to the provider's network architecture, there are two main types of video server architecture. They can be considered for IPTV deployment (configuration and implementation). Varietiesare called centralized and distributed.
The centralized architecture model is a relatively simple and easy to manage solution. For example, since all content is stored in the core servers, it does not require a complex content distribution system. A centralized architecture is generally well suited to a network that provides a relatively small deployment of a VOD service, has sufficient core bandwidth, and an efficient content delivery network (CDN).
The distributed architecture is as scalable as the centralized model, but it has the bandwidth and system management features needed to manage a large server network.
Operators planning to deploy a relatively large system should initially consider implementing a distributed architecture from the very beginning, during the IPTV connection planning phase. What does it mean? This variation requires intelligent and sophisticated data distribution technologies to increase the efficient delivery of multimedia content over the service provider's network.
Home networks
In many cases, the network gateway that provides connectivity to the Internet access network is not close to the IPTV equipment (set-top box). This scenario is becoming quite common, so providers are starting to offer packages with multiple set-top boxes for one subscriber.
Network technologies,that use existing home wiring (such as power lines, telephone lines, or coaxial cables) or wireless equipment to do this have become a common solution to this problem. Thanks to this, when connecting IPTV, setup and connection are much faster.
Benefits
The platform-based Internet Protocol provides significant benefits, including the ability to integrate television with other IP-based services (high-speed Internet access and VoIP).
Switched IP also allows much more content and functionality to be carried. So a default IPTV playlist has a lot more to offer than a regular TV program. On a conventional TV or satellite network, using video broadcast technology, all content is constantly "downstream" to each client.
The user can choose one of the proposed options - to view the broadcast on only one of the many channels of cable or satellite television. A switched IP network works differently. The content stays online, and as soon as the customer selects certain content, it immediately starts streaming.
However, this also means that customer privacy can be compromised to a greater extent than is possible with traditional TV or satellite networks. The mechanism of IPTV technology (set-top box and its settings) itself can also serve as a tool for hackingor at least disrupt the private network.
Interactivity
The IP platform also provides significant opportunities to make TV viewing more interactive and personal. A Smart IPTV provider may, for example, offer an interactive program guide that allows viewers to search for content by title or actor name, or provide picture-in-picture functionality that allows them to view menus without leaving the program being broadcast. Spectators will be able to view statistics and scores while watching a sports game or control the camera angle.
Users can also access to view photos or listen to music on their TV by syncing it with their computer, or even set up parental controls.
In order for the interaction between the receiver and the transmitter, a feedback channel is needed. In this regard, terrestrial, satellite and cable networks created for television do not allow interactivity to be connected. However, this may be possible by combining television networks with data networks.
Video on demand
IPTV Technology Smart TV also offers Video on Demand (VoD) technology, which allows the customer to browse an online program or movie catalog to select a specific entry. The broadcast of the selected item starts almost instantly on your TV or PC.
From a technical point of view, when a client selects a movie, a unicasta connection between a client decoder (set-top box or PC) and a transmitting streaming server. Signaling for control functionality (pause, slow motion, rewind, etc.) is provided via RTSP (Real Time Streaming Protocol).
The most common codecs used in VoD IPTV player are MPEG-2, MPEG-4 and VC-1. In an attempt to avoid content piracy, VoD content is usually transmitted encrypted. Although encryption of satellite and cable television broadcasts is an old practice, the advent of IPTV technology can be seen as a form of digital rights management. A movie that has been selected, for example, can be played for 24 hours after payment, after which the video becomes unavailable.
IPTV based on converged services
Another advantage is the ability to integrate and converge. It is enhanced by the use of IMS-based solutions. Service convergence involves the interaction of existing services to create new value-added ones.
