What is IPTV (Internet Protocol Television) and how does it work?

IPTV content is often delivered over a managed or dedicated network, such as a digital subscriber line connection. Compared to the public Internet, a private network gives network operators more control over video traffic, and thus the ability to guarantee quality of service, uptime, bandwidth, and reliability.

In traditional broadcast television, all programs are broadcast simultaneously in a multicast format. Available program signals flow downstream, and viewers select programs by changing the TV channel.

In contrast, the IPTV service only transmits one program at a time, i.e. unicast format. The content remains on the ISP’s network, and only the software chosen by the end user is sent to the user’s device.

When the viewer changes the channel, a new stream is sent from the provider’s server directly to the viewer. Like cable TV, IPTV requires a set-top box or other hardware for customers’ premises, such as a Wi-Fi router, fiber-optic connection, or broadband Internet connection.

IPTV primarily uses IP multicasting with the Internet Group Management Protocol for live TV broadcasts based on IPv4 and the real-time broadcasting protocol for on-demand programmes. Multicast Listener Discovery is used on IPv6 networks. Other popular protocols include Real-time Messaging Protocol and Hypertext Transfer Protocol.