The Internet is a network of computers and allows the transmission of digital data (zeros and ones). Every computer on the Internet can potentially communicate with another computer on the network. However, to do so, the two computers must follow and understand a prescribed set of rules as to what the digital data being transmitted means (i.e. are the zeros and ones components of a picture, a word, or a sound). These communication rules are normally called a protocol. Different services on the Internet make use of different protocols for communicating information or data. For example, the Web is a service that runs on the Internet (e-mail and chat are two other examples of services that run on the Internet). For you to be able to view websites, you need to have a program on your computer – called a Web Browser – that understands and follows the Hyper-Text Transfer Protocol (HTTP). This is the protocol used by the Web for requesting and sending information (i.e. web pages). Every website is accessed by connecting to the Web server that is hosting the site. A web server also understands HTTP, but its main aim is to respond to requests by sending web pages to sources of requests (hence a server), whereas a web browser is a client and mainly sends requests for web pages to web servers and then receives them (electronically) and renders (shows) them on the computer screen for its user.

The Web is only one of the services that runs on the Internet. This service uses HTTP for its communications and works through interactions between clients and servers. An Internet chat system runs on the same network that the Web runs on (i.e. the Internet), but the way it works is somewhat different. Chat systems use various protocols (e.g. the protocol used by MSN Messenger is different to that used by Yahoo! Messenger) and while they also use client and server software, the client software also acts as a server. This is especially the case in voice chat systems. With voice chat services, each client sends and receives sound/voice data in a more symmetric way (i.e. a lot of data goes both ways). There are also special servers used in chat services to synchronise clients and to register their logging in and out.

You can think of a mobile telephone network in a similar way to the Internet. There are many mobile telephones on the network that can communicate with each other. The telephones normally act like clients do in a voice chat system on the Internet. They are registered with a network and can communicate with each other through this network (N.B. for the sake of simplicity I am ignoring the fact that people on other networks can also be contacted). Just like the Internet, mobile telephone networks are (now-a-days) digital and send and receive zeros and ones, so for different mobile telephones to be able to communicate with each other, they need to understand a specific protocol. By coming up with more protocols, the mobile telephone network can be used to cater for more than just voice calls. For example, it is possible to use the mobile telephone network to transmit text messages, picture messages, or video calls. This is especially the case with the 3G (3rd generation) mobile telephone networks, as they have the capability of transmitting more data and higher speeds than older systems. Because of this, a greater number of services can be implemented on the 3G mobile telephone network than it was possible to do with older generations of networks. As you should be able to imagine, with the right protocols, it is possible to set up servers on the mobile telephone network that can provide their clients (mobile telephones and their users) video streams. These could be either in the form of pre-recorded TV programs or live television. However, as you may know from experience of watching TV through the Internet or video conferencing with a mobile telephone, such services require the transmission of a lot of data, which slows down the network and anything else you might be trying to do on the computer or the mobile phone.

Luckily, new digital broadcast standards, mainly DVB-H (digital video broadcast, hand-held), can be used to decrease the load on the mobile telephone network. Just like it is possible to connect a computer to the Internet and also install a TV tuner in it so that it can, at the same time, receive TV signals and display them as images on the screen, it is possible to install a TV tuner in a mobile telephone that can receive TV signals at the same time as receiving mobile telephone signals through its mobile telephone communications circuitry. This way, mobile television can be separated from other mobile telephone services (reducing the load on them). Work has already started on producing separate digital TV tuners that are built into mobile telephones. Digital TV broadcast signals will then be transmitted separately but in parallel with the normal mobile telephone network signals and will be picked up by these new TV tuners instead of the normal mobile telephone communications circuitry within the mobile telephone. It should be noted that mobile television broadcasts are independent of normal digital television broadcasts. This is because mobile telephones, with their limited power resources and display capabilities, as well as their ability to be moved around the World cannot be easily made to make use of the same television digital television signals as used by normal mains electricity powered televisions. So while DVB-T (digital video broadcast-terrestrial) may be used for transmission of terrestrial digital television channels, DVB-H will be used for transmission of digital television for hand-held devices such as mobile phones. Due to this separation of digital television broadcasts, it should not be assumed that watching TV on a mobile telephone will necessarily be free. In fact, parts of the DVB-H standard deals with purchasing of TV services by mobile telephone users.
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It is not actually a live broadcast but a recorded one being streamed to your device.
If you compare the Mobile Video Live streams to your TV at home, you will notice a slight delay. The delay occurs due to the need for Mobile Video to process the broadcast before sending it out to your device.
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