IPTV (Internet Protocol Television)
A telco IPTV service is usually delivered over a complex and investment heavy walled garden network, which is carefully engineered to ensure bandwidth efficient delivery of vast amounts of multicast video traffic. The higher network quality also enables easy delivery of high quality SD or HD TV content to subscribers’ homes. This makes IPTV by default the preferred delivery platform for premium content. However the investment for a telco to build an end-to-end IPTV service can be substantial.
An IP-based platform also allows significant opportunities to make the TV viewing experience more interactive and personalized. The supplier may, for example, include an interactive program guide that allows viewers to search for content by title or actor’s name, or a picture-in-picture functionality that allows them to “channel surf” without leaving the program they’re watching. Viewers may be able to look up a player’s stats while watching a sports game, or control the camera angle. They also may be able to access photos or music from their PC on their television, use a wireless phone to schedule a recording of their favorite show, or even adjust parental controls so their child can watch a documentary for a school report, while they’re away from home.
In India MTNL , BSNL, Reliance, Airtel provides IPTV services.
DTH - (Direct-To-Home television)
In DTH, TV channels will be transmitted from the satellite to a small dish antenna mounted on the window or rooftop of the subscriber's home. So the broadcaster directly connects to the user.
DTH can also reach the remotest of areas since it does away with the intermediate step of cable and wires (cables) that come to your house.
In general, DTH service is the one in which a large number of channels are digitally compressed, encrypted and beamed from very high power satellites. The programmes can be directly received at homes. This mode of reception facilitates the use of small receive dish antennas of 60 to 90 cm diameter installed at convenient location in individual buildings without needing elaborate foundation /space etc. Also, DTH transmission eliminates local cable operator completely, since an individual user is directly connected to the service providers. However, a digital receiver is needed to receive the multiplexed signals and view them on a TV. DTH, in sharp contrast to Cable TV, lends itself to easy monitoring and control.