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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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