Hot Streaming HDTV

As I mention in my current column, streaming high-quality A/V content in real time over the Internet is not practical due in part to bandwidth limitations. Currently, DSL and cable modems top out at about 3 megabits per second downstream (into the home), while DVDs typically consume 4-7Mbps of bandwidth, and standard MPEG-2 HDTV requires over 19Mbps.

This week, the broadband bottleneck opened quite a bit wider. The International Telecommunication Union (ITU) has ratified a new high-speed standard called VDSL2 (Very-high-bit-rate Digital Subscriber Line 2), which is said to reach speeds of up to 100Mbps both downstream and upstream. Amazingly, VDSL2 is intended to operate on standard copper telephone cable using existing equipment.

According to Yoichi Maeda, chairman of the ITU Telecommunications Standardization Sector (the group conducting the work on VDSL2), "This new standard is set to become an extremely important feature of the telecommunications landscape, and is a landmark achievement for our members, many of whom are relying on this recommendation to take their businesses to the next level."

In a statement, Michael Brusca, chairman of the DSL Forum, said, ""With vendors' implementation of this new ITU-T Recommendation, service providers can offer even more high quality, advanced services using DSL technology. It represents another essential element in the delivery of universal broadband access for multiple applications in every region of the world and demonstrates the continuing dynamic development of the technology."

The DSL Forum, a consortium of equipment manufacturers and service providers, recently reported that there are now more than 100 million DSL subscribers worldwide, more than a third of which were added in 2004 alone. The DSL Forum predicts that VDSL2 will provide speeds of 25Mbps to most subscribers, with 100Mbps available over short distances.

With speeds like that, HDTV can easily be streamed in real time right into your home, coexisting seamlessly with other forms of Internet content, VoIP (Voice over Internet Protocol) telephone service, and video conferencing. The potential of this technology is so huge, BellSouth has already announced plans to use it with the systems they've installed over the last 10 years. With VDSL2, the promise of "convergence" might finally be realized.