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Re: Re: [sarex] APRS/MIR School Day Roundup, Day 1.




 
> I really WISH that there was MORE known about
> UNPROTO UI frames!
> 
> It is strange, because it is so SIMPLE!
> 
> Unconnected UI frames (APRS STYLE) have much MORE
> potential than those RETRIES on a packet connection!
> 
While I agree, I don't think it is has nearly the clearcut advantages that the faulty statistics 
seem to predict. The reason is that when 2 people are trying to communicate via UI, and you 
see a UI packet appear on MIR, you have no idea of whether the person on the other end is 
actually receiving the packet. I used MIR a lot to send 1 line hello packets to people, and UI is 
just fine for this, but on the occasions that I have tried to have a real multi-line conversation with 
another ham, I quickly came to the realization on both ends we were missing packets sent 
from the other end. What we ended up having to do was to send each packet twice to make 
sure it got through. Ie to have a multi line conversation some sort of error checking or receipt 
acknolegement is requirred or else you end up wasting bandwidth with repeats. If you employ 
the complete APRS style ack protocol, it would in all liklihood be as of bandwidth as regular 
connected protocol, although this would depend on the circumstances.
.....
> Bob Bruninga is the "PIONEER" on unproto techniqies
> (APRS)
> 
 
Unfortunately, this isn't completely accurate, and is part of the reason why unproto isn't used 
more on MIR.  Bob is certainly the Pioneer of APRS, but unproto techniques have been around 
long before APRS. APRS is a communications technique that USES unproto packets. The 
complete APRS communication protocol employs receipt acknolegements, beacons and all 
sorts of other non info packets that would clog up the limited MIR bandwidth if everyone used it. 
In the past there has been a lot of resistance toward use of APRS on MIR for this reason, and 
unfortunately, because many people think that APRS and UNPROTO are the same thing, there 
was also criticism of people who used unproto. Particularly if APRS compatable information 
was included in the packet. This is unfortunate.
   I think it is important to understand that there is a difference between communicating via 
APRS and communicating with APRS STYLE PACKETS. I HOPE that no-one really thinks it is 
conceivable to have everyone on MIR running an APRS program....that just won't work. I think 
that what is WILL work on MIR is for people to use the APRS style UI packets. Ie simply 
include grid square or lat/lon in a way compatable with people monitoring with one of the APRS 
mapping programs.
   The reason I make this point is that for years, people used UI packets on MIR, often putting 
their name as the "To:" part of the address, and no-one complained, but as soon as people 
started putting APRS style information in the packets, some people would equate that to 
"running" APRS, and send up nasty packets telling people that APRS wasn't allowed. It is 
apparent that many people still confuse APRS with unproto. They aren't the same thing. I think 
if more people understood the difference there would be more effective use of the technique.




+----------------------------------+
| Bill Jones, N3JLQ,Sweden, Maine  |
| wejones@megalink.net             |
| http://www.megalink.net/~wejones |
+----------------------------------+
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