lml2000
Whazzup
join:2000-08-17
Los Angeles, CA
 ·RoadRunner Cable
|  reply to Jerm
Re: This is what ADSL was designed for!
First, one must make a distinction between video-on-demand (VOD) and multichannel broadcast. Single channel VOD can be accomplished quite easily over a 6 Mbps. Multichannel broadcast requires in the neighborhood of 30-35 Mbps, I believe, and as result would require a VDSL platform that is predicated upon much shorter copper loops, let's say about 1,500 to 2,500 feet. Where there is no VDSL, there will be no multichannel broadcast. However, where there is only DSL, there can be VOD, but I believe a 4-5 Mbps connection is necessary.
If you study Project Pronto's architecture you would note that if desired, a subscriber can chalk up extra cash and get a 6 Mbps asymmetric downstream connection rather than the basic 1.5 Mbps. However, regardless of your subscription rate, on a switched basis your 1.5 Mbps DSL connection DSLAM'd to your ISP's POP can be upsized to a 6 Mbps and re-routed to a video server such as Blockbuster's and reading to pump a video-bit stream to your TV monitor . . . on demand. You can pause, rewind, etc. With the aid of local buffering , the actual content can either be delivered from a remote server or stored locally on a hard drive for your TEMPORARY use.
When you talk about DVD or HDTV video, do you know what you are really referring to? Most in the business refer to DVD as delivering a 480p (p=progressive) picture. This is in contrast to standard TV, which is 480i (i=interlaced), and HDTV which comes in 780p and 1080i formats. But really, at this point in time, when we are talking about VOD, which is streaming bits of data down over a DSL connection, why even consider HD? We'll get there, but first things first. The MSOs are loathe to deliver HD signals over their pipes because of the bandwidth it sucks up at the cost of other programming, and therefore advertising. HD is limited right now, and IMHO, will be in the foreseeable future until broadcasters are forced to drop analog broadcasting by 2008, I believe.
Nevertheless, VOD over DSL is the first step toward the ultimate HD video goal. But remember, Rome was not built overnight.
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Regards,
lml |
