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[aprssig] Bandwidth IS THE FUTURE OF APRS

Rick Green rtg at aapsc.com
Thu Oct 12 16:27:25 UTC 2006

On Thu, 12 Oct 2006, wa7nwp wrote:

>>> I do agree that the above beacon is
>> absolutely wasteful of bandwidth!
> We have to change the way we look at things.
> YouTube feeds 100 MILLION!!!  Videos a day.   Those Videos are in Megabytes. 
> (You all saw the dramatic 4th episode of Chad Vader - right?)
   Yes, and it feeds it over fiber, on clean point-to-point links, without 
CSMA issues, not to mention hidden-transmitter issues, etc.
   Also, YouTube, and other video-on-demand sites, as well as various 
IP-streaming audio and video sites, are themselves bandwidth-limited, in 
that separate bandwidth is needed for each simultaneous user.  Traditional 
RF broadcasting is much more appropriate for mass distribution of media.
> It's 2006.  We're still running 1200 baud  (nope - didn't forget the K at the 
> end of that -- hard to believe.)   We panic if somebody actually adds an 
> extra hop to their path.  Here we're counting fraking bytes in a status 
> packet.
   Because on a 1200baud radio channel, those bytes matter.
> We have incredible technology just waiting to be put to use.  We have dozens 
> of vastly underused channels.  We probably have Megabytes in the Microwave 
> spectrum that's dead dead dead.
   We DON't have the technology sufficiently developed.  My meager 
experiments with 9600 baud told me it's extremely difficult to keep a 
single link up over a 20-mile path using directional antennas.  The 
sensitivity of these modems to frequency stability, seleective fading, 
etc., tells me we're a long way from practical mobile high-speed packet.
   We could adopt the techniques that are being implemented by the digital 
cellular carriers for high-speed mobile digital transmission, but many of 
those are patent-encumbred, so we have to start from scratch and develop 
our own.
> Lets work on moving on - not digging a deeper hole then what we already have.
   Agreed, but from where we're at, the development needs to happen first 
on building a stable high-speed backbone.  Unstable mobile stations will 
come later.

> Quiet air is wasted air - make packets!
   This sounds to me like the same kind of attitude that's got our roads 
clogged with inefficient, gas-guzzling SUV's, and our children killed 
trying to secure the oil to fuel them.
   I plea for appropriate use of the technology at hand, and careful 
adoption of newer technologies that are actually better, not just bigger 
for the sake of our egos.

Rick Green,  N8BJX

"Those who would give up essential Liberty, to purchase a little
temporary Safety, deserve neither Liberty nor Safety."
                                   -Benjamin Franklin

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