Why do people you've never met decide what you can watch on TV and when? Sure, there is always a choice of channels, but the choice is quite limited. Unless you record the program in advance, you can only watch it when the program is broadcast. Wouldn't it be better if watching TV is more like browsing the web, so you can choose the program you want to watch anytime, anywhere? This is one of the promises of IPTV (Internet Protocol Television). It uses Internet technology to deliver TV programs on demand. How does it work? What benefits will it bring us? What challenges will broadcasters and telephone companies face in delivering these new services? Let's take a closer look!
What is IPTV?
From the perspective of TV viewers, IPTV is very simple: it does not receive TV programs from roof antennas, satellite antennas or fiber optic cables as broadcast signals to enter your home, but streams them through your Internet connection (download and play almost at the same time). It's not the kind of connection you have now, it might only handle 1-10 Mbps (megabits per second is about the amount of information that goes into your computer's novels on average per second!) But the bandwidth (information carrying capacity) of the broadband line is about 10 times of 10-100mbps. You can watch the program on your computer, or use a set-top box (an adapter for your Internet connection and your existing TV receiver) to decode the input signal so your TV can display the Internet program.
IPTV is a little more complex from a broadcaster's or phone company's point of view. You need a complex storage system to store all the videos you want to provide, as well as a network-style interface so that people can choose the programs they want. Once the audience selects a program, you need to be able to encode the video file into a format suitable for streaming media, encrypt it (only those who pay can decode and receive it), embed ads (especially when the program is free), and transmit it to anyone (potentially) thousands of people or millions of people at a time via the Internet. In addition, you have to figure out how to do this in order to provide a consistently high-quality picture (especially if you are offering ads with your programs, as this is something your paid advertisers will definitely look forward to).
Three types of IPTV
IPTV has three different styles. The first, which you may already be using, is called video on demand (VOD). With services like Netflix, you can choose a TV show or movie that you want to watch in a wide range, pay for and watch there. Some of the world's more aggressive broadcasters are launching another IPTV. In the UK, the BBC uses an online streaming video player called BBC iPlayer to play last week's shows online. This service is sometimes referred to as time-shifted IPTV because you watch regularly scheduled broadcasts at a convenient time. The third type of IP TV includes live TV programs on the Internet, because they are being watched, so it is "live IPTV" or "IP simulcasting". All three forms of IPTV can use your computer and a normal web browser, or (for better quality) a set-top box and a normal digital TV. All three services can be delivered over the public Internet or hosted private networks that work in essentially the same way (for example, from your phone and Internet service provider to your home entirely through the provider's network).
What is the "Internet Protocol" on IPTV?
IPTV stands for internet protocol TV, but what does "Internet Protocol" mean? This is the essence of Internet operation.
Send an email to a friend or download a web page, and the information you start won't spread as much as you expect. Instead, it is divided into many small pieces, called packets, each of which can be "exchanged" (sent) to a destination via a different route. As we all know, packet exchange is the basic principle of any information dissemination on the Internet. The computer that connects the network does not know what any given packet means or what it does. They only know the IP address (every computer on the Internet has a number "house and street name"), where packets have to be delivered, and they treat all packets the same.
The Internet is not designed to do something, such as sending an e-mail: it's just an efficient, computerized "post" system for sending millions of packets. The simple but amazing result is that as long as you can turn information into packets, you can send any possible information over the Internet. That's why the Internet can be used to send e-mail, Download Web pages, make phone calls (using a technology called "VoIP"), watch TV and do more than a dozen other things that have not yet been invented. If someone designs the Internet more strictly just to send and receive an e-mail, such as using it for other things, such as making a phone call or watching TV, it may not be possible.
How does IPTV work?
In traditional TV, programs are converted into radio waves, which are transmitted through the air to your roof antenna. The antenna converts the radio wave back to the electric signal, and your TV decodes it to produce sound and image (the principle of satellite TV is the same, except that the signal will be reflected to the space and back, while cable TV will send the signal directly to your home, without the radio wave).
How to stream IPTV
In order to watch IPTV content, you need a device to receive and decode the stream and a connected source that serves the channels, movies, and sports broadcasts you want. There are three devices that let you access streaming content:
Smart TV
Mobile phones and tablets
Set-top box
Stored program
Live programs will be streamed during production, but pre-recorded programs and movies need to be stored in a way that can be selected and streamed on-demand. Some VOD services limit the number of programs they provide, not because they lack storage space, but because it is a way to limit the total bandwidth of their services and their impact on the Internet. (for example, if the BBC offers every program it produces on its iPlayer for free, a large part of the Internet bandwidth across the UK will be consumed by streaming soap operas and sitcoms, which may slow down every kind of network traffic on the network.)
GTV IPTV provides recording function: cloud PVR self-storage, which can be permanently saved. To learn more about the GTV recording function, you can watch REC Guide on GTV IPTV Blog.
Preparatory procedure
First of all, TV programs (pre-recorded or filmed on-site by the camera) must be converted to digital format, which can be transmitted as data packets using internet protocol. Sometimes the original program is already in digital format; sometimes it will be a standard analog TV picture (called SD format), which needs additional processing bits (analog-to-digital conversion) to be converted into digital format. Due to the current bandwidth constraints, the video also needs to be compressed (compressed into smaller files) so that it can be transmitted smoothly without buffering (periodic delay caused by the receiver when establishing incoming packets). In fact, this means that the program is encoded in MPEG-2 or MPEG-4 format (MPEG-4 is a relatively new form of video compression, which provides higher quality for similar bandwidth, and the bandwidth required to carry SD pictures is only half of MPEG-2). Once this is done, the ad must be inserted and the information must be encrypted.
Streaming program
When you browse a website, you actually set up a temporary link between two computers so that one computer can "suck" information from the other. Your computer (client) obtains information from another computer (usually a more powerful computer) by directly linking to an IP address corresponding to the website you want to browse. There is a short, intermittent conversation between the client and the server in which the client requests from the server all the files it needs to build the page you are viewing. Servers are usually so fast and powerful that many clients can download in this way at the same time with little delay. This common download between a client-server and a server is called "IP unicast" (which most web browsing falls into).
IP Multicast
However, when it comes to streaming media (playing programs when downloading programs), the client creates a greater (simultaneous) load on the server, which can lead to unacceptable delays and buffers. Therefore, in streaming transmission, a different download method is used, which is called "IP multicast", in which each packet leaves the server only once, but is sent to many different destinations at the same time; in theory, this means that one server can send information to multiple clients as easily as to one client. Therefore, if 1000 people watch the World Cup finals on the Internet at the same time, they will receive streaming video packets from a server and send them to 1000 clients using IP multicast. If the same TV provider offers an episode of friends at the same time, and some of the first 1000 people decide to "switch channels" to watch it, they actually switch from one IP multicast group to another and start receiving different video streams.
The global nature of the Internet makes it difficult to send information from servers to local clients as reliably as to clients on the other side of the globe. That's why IPTV providers often use asynchronous global network on their servers, the so-called content delivery network (CDN), which keeps a "mirror" copy of the same data; then, people in the United States may stream programs from mountain view in California, while people in Europe may get them from Frankfurt in Germany.
IPTV protocol
When you stream a program, you don't download it like a normal file. Instead, you download a file, play it, and when it plays, download the next part of the file, ready to play in a minute or two. None of the files have been kept for a long time. Streaming works because your computer (the client) and the computer it receives data from (the server) agree to do so. The Internet has successfully connected almost all computers in the world because they all agree to talk to each other in the same way using pre-arranged technical programs called "protocols". Streaming media does not use normal, standard, web-based download protocols (technically, their names are HTTP and FTP), but uses protocols suitable for downloading and playing at the same time, such as RTP (real-time protocol) and RTSP (real-time streaming protocol). Multicast streaming includes using IGMP (IP group management protocol; you occasionally see books and web pages that replace m with "membership"), which allows a server to broadcast to members of a group of clients (in fact, many people are watching the same TV channel).
Managed network
Making IPTV available on the public Internet is very different from delivering through private and managed networks. Many IPTV providers will choose to do so eventually: by controlling the whole network, they can guarantee a certain quality and service levels. In fact, this means having a highly organized, hierarchical network with a national office called the "super front end" (she) that powers a regional center called the video center office (VHO), which in turn serves local distribution offices connected to individual family set-top boxes.
View program
Everyone with a computer and broadband Internet connection can watch IPTV, but most of us don't want to watch TV on a rough laptop screen. That's why the future of IPTV is likely to involve viewers buying set-top boxes (sometimes referred to as set-top boxes), receiving input from Internet connections (via Ethernet cables or Wi-Fi), decoding signals, and displaying pictures on HD widescreen TVs. The set-top box is actually a kind of independent computer. When programming, it only does one thing: receiving streaming video packets, decrypting them, converting them back to video files (MPEG2, MPEG4 or any of their original formats), and then displaying them as high-quality TV pictures. Apple TV is widely used in this way, using set-top boxes to run simple applications on a simplified operating system (tvos), which manages the process of video transmission over the Internet.
As a simple, more compact, more discreet alternative to set-top boxes, you can use the so-called dongle, which looks a bit like a USB flash stick but allows secure access to Internet TV programs. The dongle plugs into the HDMI (high-speed, high-definition digital video) outlet on your TV and connects to the Internet via Wi-Fi to play TV programs, movies, and music director. Some dongles are completely self-sufficient: Roku and Amazon firework-like this without any help from computers or mobile devices. Google's chrome cast is a little different: Generally speaking, you can use your computer, tablet or smartphone (it actually becomes a remote control), and then it transmits your movies or TV programs directly from the Internet.
What's the difference between a set-top box and a dongle? Simple: the set-top box is a larger box with a faster processor and more memory, so it can provide higher quality video output; this makes it more suitable for high-performance games, etc. Some companies, such as Amazon and Roku, offer either a simple, relatively expensive dongle or a more expensive, higher specification set-top box.
Fortunately, IPTV's development may be exactly the same as the development of broadband Internet in the early 21st century: at that time, as more and more people use the Internet, they felt hindered by the restrictions of dial-up connection, demanded (and indicated that they were willing to pay) higher quality broadband, and provided enough revenue for telecommunication companies. Upgrade their network. Once the audience begins to experience the convenience, control, and interaction of IPTV, the Internet connection with higher bandwidth seems certain to follow.
GTV IPTV - "the most reliable IPTV service" for HD streaming
GTV or GTV IPTV for short has almost become a household name in IPTV streaming. They use highly customized web streaming services and highly reliable streaming services to run quite complex services.
What's more impressive is the video on demand part, which covers more than 2500 films and more than 500 TV plays. GTV IPTV over 1000 very important live channels. Show the important channels and sport event channels. However, what distinguishes radio and television from other services is their sporting events. This is their own "live sports" list, each of which has multiple link channels.
Last but not least, GTV Plus(red) over 160 channels 7 days catch up+ important sports and events., allowing you to watch anything you might miss.
As you know, GTV IPTV is not a joke in terms of function. Fortunately, the quality and reliability of this service are not high. They have been around for a long time and know-how to run IPTV services.
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