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Bandwidth hunger

Satisfying your need for speed

By Rinaldo Di Giorgio, JavaWorld.com, 10/01/96

Iam starting to spend a good part of my life waiting for things to download -- about one hour a day on average. I try to do other things during the wait but I tend to loose focus and forget what I was doing in the first place. I would like also to stop buying disks, CD-ROMs, and backup tapes all the time and start using distributed objects in their stead. What does this have to do with cable modems? This is the first of a two-part series that will discuss some new developments with cable modems and provide you with some useful URLs to bolster your understanding of the technologies involved. These will help us be open minded in considering the possibility of trusting cable providers enough to let them run object databases that allow you to store and retrieve objects (see "RMI and object serialization" for some applets demonstrating the bleeding edge of using remote objects). Not some CORBA/IDL mapping but a true OD. I have been interested in cable modems for several years and giving talks on the topic to audiences that looked at me as if I was from Mars.

A number of technologies may be able to support the bandwidth this type of architecture requires soon. They are:

• Cable modems -- an introduction by Jim Connors of SunSoft. To be followed next month with an article from Howard Pfeffer of Time Warner cable. Everyone seems to be talking about it. Byte Magazine featured the topic on it's front page.
• Direct broadcast satellites
• ISDN
• ADSL

Direct broadcast

Several satellites at various positions in space transmit approximately 200 channels of digital compressed video to a small satellite dish at recipients' premises. I am not aware of any service providing the ability to transmit up since the uplink is expensive. The satellite dish you get is basically a receiver. I think that hybrid services would use a combination of say ISDN or POT to provide the interactivity. There are currently four providers of this technology. A good FAQ can be found at here. In future issues we will be talking about this technology in relation to Java.

ISDN

Both Microsoft and Sun have good pages and products on ISDN. Sun actually provides many employees with ISDN access to the corporate network. Sun started shipping ISDN several years ago but then the industry wasn't ready and in many parts of the country it still isn't available. A good collection of ISDN links is available at here.

ADSL

There are three technologies in this area and they are designed to meet different networking requirements. Several phone companies are actively pursuing solutions. A very comprehensive source of information at ADSL can be found here. Another very good link can be found at the ADSL forum. Finally, here is a late-breaking news item.

Summary

The necessary bandwidth is not really available yet for consumer applications. Just the other day someone was showing me a thumbnail of video and trying to convince me that it was video -- granted, it worked at 28.8 kbps but it had the usual problems, required a native client-side program, and was so tiny I thought it was an animated GIF.

 

XpoLog Center Correlate application logs with server metrics - XpoLog

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