Satellite's Four IP-TV Solutions.

The penetration of personal PCs and Internet connections is much higher among cable and satellite homes than in others, and this is true of all countries. [In Europe, there are] 67 million [homes subscribing to] cable and 45 million [to] satellite, meaning that in Europe, 38 percent of [all TV] homes receive programs by cable or by satellite.

As this [technological] transition unfolds, it is the duty of service providers to implement simple, efficient and cheap solutions that will truly permit the advent of broadband services. The 56 kbps digital rate of users' modems is not sufficient: 250-500 kbps is the minimum required for the transmission of acceptable-quality video images. Therefore, high growth is foreseeable for broadband access providers, proposing either wired (DSL, cable) or wireless (satellite, UMTS) technologies. It is predicted that broadband access will soon become one of the main drivers of Internet growth.

However, a drawback to broadband is the very high cost of implementing a "rich media" interactive content offering for a large online audience. The cost of connection between the site and the Internet backbone increases proportionally to the number of users visiting the site simultaneously. This fact confirms that the Internet is mainly a telecommunications network rather than a broadcasting infrastructure.

Currently, there are four solutions:

The first solution is based upon a hybrid architecture, combining the use of a satellite on the network-to-end-user path, and of a modem and terrestrial connection on the end-user-to-network path. Instead of transmitting video to everyone, Internet parcels are sent to specific Web users. The advantage is the complete decongestion of the access networks. The drawback is a relatively higher cost to the user, because the satellite connection cost, set up in a mode known as "unicast," is not shared.

A second solution calls upon satellites for what they are best suited for: broadcasting. In the Internet vocabulary, however, this is known as "multicasting," while programs are "content" and channels are "streamed videos." In this proposal, the IP standard continues to be used. The main advantage is its significant economy for a [programmer] -- in such multicast streams, the satellite bandwidth is shared between all users. The main drawback is that interactivity is restricted to switching from one video stream to another. In fact, many of today's satellite services combine the first and second solutions, offering the advantage of broadcasting wideband content economically and surfing on the Web.

The third solution also focuses on this hybrid architecture but includes the possibility of storing content on servers and cache memories. Such a solution is more promising for a few reasons. Most files present on websites do not need to be updated more than every three hours. This solution applies to direct-to-home (DTH) reception, where the satellite directly feeds and updates the disk and memory of the terminal. Such a concept is used in the U.S. by TiVo. Rich media and web TV [programmers] will be able to route their content economically to those servers, again thanks to the satellite's ability to provide multicast connections.

The fourth solution offers users, particularly those in rural areas, a fully satellite-based solution. The receiving dish becomes a transmitter, thus enabling the satellite to be used as a broadband access loop to the Internet. For such a solution to be acceptable, cheap terminals will naturally be required. Following the great success of its digital broadcasting standard, the DVB standardization group has drawn up a similar standard for such interactive satellite terminals.

EUTELSAT is developing a satellite whose design will be optimized for the supply of broadband IP services. This satellite, to be known as IPSAT, will enable the various solutions described above to be combined.

This is an excerpt from a presentation delivered at the Broadband 2000 Conference last October in Paris, France.