Today, you can increasingly hear about a service such as interactive television or IPTV. What it is? IPTV is a system through which television services are provided using a set of Internet protocols over a packet-switched network (local or global), instead of transmitting data using traditional terrestrial and satellite signals, as well as cable formats. Unlike downloadable standard media, interactive TV offers the ability to stream information in small, sequential volumes, coming directly from the source. As a result of this, the user can start playing back data (for example, a movie) before the entire file is transferred. This is also known as streaming media.
Answering the question “IPTV - what is this?”, It should be noted right away 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 subspecies:
- Live broadcast from the current TV broadcast.
- Television in the past mode: repeats of TV programs that were broadcast several hours or days ago, as well as repeated playback of the videos you just watched.
- Video on Demand (VOD): The ability to view a catalog of videos not related to a television program.
IPTV - what it is: technology definition
Historically, many different attempts have been made to define IPTV. This technology is described as a combination of elementary or transport streams over IP networks, as well as a number of proprietary systems.
One of the official definitions is approved by the International Telecommunication Union. According to him, IPTV is multimedia services (television / video / audio / text / graphics / other data transmission via IPTV-player) received over IP-based networks. When implemented, it turns out to provide the appropriate level of service, security, reliability and interactivity.
According to another officially recognized source, IPTV is defined as the safe 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 on the World Wide Web, when you start IPTV, you can maintain greater security and network performance, resulting in uninterrupted broadcasting.
How did such a TV develop?
The technology was initially hindered by the low level of broadband distribution and the relatively high cost of installing wiring capable of transporting IPTV content reliably to customers' homes. Nevertheless, the use of IPTV today is becoming increasingly widespread, and the number of subscribers continues to grow.
Items
TV hardware is exactly that part in which IP television channels are encoded, encrypted, and delivered as multicast streams.
The VOD platform is the place where the assets of the video (IPTV playlist) are available, available on demand. They are activated when the user makes a request in the form of an IP unicast stream.
An interactive portal allows the user to navigate within various IPTV services (such as the VOD directory).
A delivery network is a packet-switched network that contains IP packets (unicast and multicast).
Home TV Gateway - part of the user equipment that controls the activation of the transmission of information or its shutdown.
Smart IPTV: a piece of user equipment that decodes and decrypts TV and VOD content and displays it on a TV screen.
Video Server Network Architecture
According to the network architecture of the provider, there are two main types of video server architecture. They can be considered for IPTV deployment (setup and implementation). Varieties are called centralized and distributed.
A centralized architecture model is a relatively simple and easy-to-manage solution. For example, since all content is stored in the parent servers, it does not require an integrated content distribution system. A centralized architecture is generally well suited for a network that provides a relatively small deployment of a VOD service, has sufficient kernel bandwidth and an efficient content delivery network (CDN).
A distributed architecture is as scalable as a centralized model, but it has primary bandwidth as well as system management features that are 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, at the planning stage for an IPTV connection. What does it mean? This variation of it requires intelligent and sophisticated data dissemination technologies to increase the effective delivery of multimedia content over the service provider's network.
Home networks
In many cases, a network gateway that provides communication with an access network on the Internet is not close to IPTV equipment (set-top box). This scenario is becoming quite common, so providers are starting to offer service packages with several prefixes for one subscriber.
Network technologies that use existing home wiring (such as power lines, telephone lines or coaxial cables) or wireless equipment 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).
A dial-up IP network also enables the transfer of significantly more content and functionality. Thus, the default IPTV playlist can offer much more than a regular TV program. In a conventional TV or satellite network, using the technology of broadcast video transmission, all content is constantly “flowing” to each client.
The user can choose one of the proposed options - view the transmitted only on one of the many channels of cable or satellite television. A switched IP network works differently. The content remains online, and as soon as the client selects a specific content, he immediately begins to broadcast.
However, this also means that the privacy of the client may 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) by itself can also serve as a tool for hacking, or at least cause disruptions in the operation of a private network.
Interactivity
The IP platform also provides significant opportunities to make watching TV more interactive and personalized. The Smart IPTV provider can, for example, offer an interactive program guide that allows viewers to search for content by the name or name of the actor, or provide picture-in-picture functionality, which allows you to view the menu without leaving the broadcast program. Viewers will be able to see statistics and scores while watching a sports game or control the angle of the camera.
Users can also access to view photos or listen to music on their TV, synchronizing it with a computer, or even set up parental controls.
In order for the interaction between the receiver and the transmitter, a feedback channel is required. In this regard, terrestrial, satellite and cable networks created for television do not allow you to connect interactivity. However, this may be possible by combining television networks with data networks.
Video on Demand
IPTV 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 recording. The broadcast of the selected item starts almost instantly on the TV or PC.
From a technical point of view, when a client selects a movie, a unicast connection is established between the client’s decoder (set-top box or PC) and the 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 IPTV-player for VoD are MPEG-2, MPEG-4 and VC-1. In an attempt to avoid content piracy, VoD content is usually 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 within 24 hours after payment, after which the video becomes unavailable.
Converged Services IPTV
Another advantage is the ability to integrate and converge. It is enhanced by using IMS-based solutions. Service convergence involves the interaction of existing services to create new ones with added value.