In our monthly reports, we've often written about "whole home networks"--a unified network for all digital applications.
A whole home network will need to support five categories of digital applications: video, audio, telephone, data, and telemetry/control:
Video applications include the distribution of digital video content from the broadband connection, DVD players and the home media server to any video screen in the house - whether on a PC, a TV, a game console or a Webpad. It also includes the networked connection between digital video cameras, servers, and viewing devices. The video will come in many formats including conventional "standard definition" (SD) and "high definition" (HD).
Audio applications include the distribution of digital audio from CDs, MP3 files, Internet radio and home media server throughout the house to any set of loudspeakers and headphones.
Telephone services include all forms of interpersonal voice communications. Starting with conventional voice services, it will expand over time to include call forwarding and conferencing, and later add video telephony and integrated multimedia communications.
Data applications include the shared use of Internet text and data -- mostly Web browsing, email and chat. It also includes sharing data and peripherals between PCs and other broadband appliances..
Telemetry and control includes a wide variety of applications often labelled "smart home". These include lighting and audio/video controls; external monitoring and control of electricity and gas; home security including external access to monitoring video cameras; home appliance servicing; and in-home communication between appliances.
The Home Bandwidth Budget
How much capacity is required in a home network? It helps to think about the "home bandwidth budget".
High definition video today requires 18 Mbps for each channel, probably 10 Mbps or less in the future as MPEG4 Part 10/H.264 becomes the dominant form of video coding.
Audio applications require data rates from 128 Kbps to about 1.5 Mbps (depending on compression)
Voice services require very low data rates (15-64 Kbps) while real-time video communications requires somewhat higher rates (128 to 384 Kbps).
Data applications will generally work satisfactorily at data rates of 5 Mbps or less.
Telemetry and control applications generally require very low bandwidth -- a few kilobits per second.
Thus a home bandwidth budget of 50 Mbps or so should be adequate for most households, even with several simultaneous channels of HDTV.
Standard "switched Fast Ethernet" provides throughput of nearly 100 Mbps, and all emerging home networking technologies are aiming to match its speed. This should be adequate capacity to meet the bandwidth budget needs for some time to come.