Order Tray | Contact Us | Home | SIG Lists

[aprssig] Failed APRS?

Rick Green rtg at aapsc.com
Wed Jan 21 16:18:33 UTC 2009


On Wed, 21 Jan 2009, Jack Spitznagel wrote:

> So instead of slicing definitions and seeking the "original text" like a
> bunch of alchemists clustering around a calderon... Lets FIX the problem
> instead of wasting bandwidth!
> -the curmudgeon - kd4iz
   That isn't going to happen within the current definition of the APRS 
spec.  As I see it, the real problem is that we're trying to fit a square 
peg into a round hole, and it's just not going to work without something 
breaking.
   We can argue forever about semantics, but let's look at the technical 
side instead.  It all comes down to the fact that the APRS 'network' is 
non-routed, and is based on a multi-hop broadcast topology.  Every packet 
is disseminated in every direction from its source.  This is appropriate 
technology for a 'tactical, situational awareness' system, but is totally 
inefficient and clearly inappropriate for any point-to-point messaging. 
The congestion we complain about is of our own making.

   Now I know that SMS messaging is the 'killer app' that has made APRS so 
wildly popular, and a great number of you don't want to hear me say this, 
but SMS messaging on APRS, in my opinion, violates the long-held principle 
in amateur radio of using the 'minimum power necessary to accomplish the 
communication'.

   I support the development and implementation of standards for the 
inclusion of 'presence' information within an APRS broadcast message, such 
as the 'operator present' bit, voice alert, etc.  We need to develop as 
well a convention for the description of the preferred, and possibly 
multiple, mode/frequency/address tuples for possible direct communication. 
Only when we have a standard for the broadcast dissemination of a 'link' 
to a direct communication channel, can we proceed to develop auto-QSY 
software for our frequency-agile mobile rigs.  Then we will have the 
'universal mobile communications platform' that some try to believe can be 
shoe-horned into the APRS spec alone.

-- 
Rick Green, N8BJX

"Those who would give up essential Liberty, to purchase a little
temporary Safety, deserve neither Liberty nor Safety."
                                   -Benjamin Franklin
"As for our common defense, we reject as false the choice between our 
safety and our ideals."
                                  -President Barack Obama, 20 Jan 2009



More information about the aprssig mailing list