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Residential Broadband Evolution

Many services envisioned for the NII will demand significant amounts of communications bandwidth. To extend these services to the general public, broadband access networks to private residences and apartments will play a critical role in the NII. Residential broadband (RBB) networks are already widely deployed for entertainment video distribution services. Future residential broadband networks will provide increased bandwidth and two-way interactive capabilities supporting a wide variety of applications.

To characterize today's RBB networks and to understand how they are evolving to provide the capabilities needed in the future NII, the XIWT invited industry experts representing CATV companies, local exchange carriers, RBB equipment manufacturers, and satellite communications service providers to discuss current and future RBB networks.

The following is a summary of the views of these industry experts. It does not necessarily represent the views or positions of the XIWT or its member companies.

Residential Broadband Today

Access Architecture

Today's residential broadband (RBB) is composed of over-the-air broadcast networks, CATV networks, microwave access networks, and direct reception from home satellite antennas. With the exception of emerging satellite-based delivery systems, today's RBB access networks are based on 6-Mhz analog channels. In a recent study of CATV networks conducted by CableLabs, typical downstream capacities were as follows:

22 percent have less than 30 channels;

64 percent have 30 to 53 channels; and

14 percent have 54 channels.

Although the amplifier housings employed in current CATV networks are designed to accommodate a return path amplifier (i.e., they are two-way ready), most of today's CATV systems have unactivated return channels. Roughly 20 percent of today's CATV systems use some fiber-optic links to bypass long amplifier chains in the trunk portion of the network. Currently a mix of 300-, 400-, 450-, and 550-MHz amplifiers is used. Service is typically provided to residences and apartments, with relatively few business locations connected to CATV networks. There is usually only a single CATV operator in a given service area, with nascent competition from microwave and direct broadcast satellite service providers. TVRO (television receive only) background antennas that are 1 to 2 meters in diameter are used by a small fraction of residential customers.

Services available over today's RBB networks typically consist of the following core set:

Basic video;

Subscription pay;


Special events; and

Shopping channels.

In addition, the following emerging services have been deployed on a limited basis:

Near video on demand;

Electronic video guides;

Low-speed and high-speed data access;

Digital video services via high-power satellites; and

High-speed, downlink-only data via high-power satellites.

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