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Re: ISS Unproto Destination Address

On Wednesday 26 September 2001 10:38, Stan Vandiver wrote:

> I don't believe it is the sender's responsibility to make sure he is
> seen on the network, as you describe.  

Well, if you don't *wish* to be seen by APRS stations, there's 
absolutely no reason why you should follow APRS formats.

> Not an "open" network anyway.  APRS is not an "open network" in my 
> opinion... 

It is "open" in the sense that we use that term in a networking 
context. All the details of the protocol are published, and anyone is 
free to implement them...or not. If you *do* use them, it does make 
sense to implement them in such a way as to be a good network 
citizen...that is what FCC would call "good amateur practice". If you 
*don't* care to use them, then don't.    

>  APRS should have that same capability.  You need an
> "ANY" subset, or in other words, an OFF button, to turn off the
> filter.  You will let APRS configure any subset except this one.

We have *several* addresses that function this way....just like IP has 
broadcast addresses. 

>  The pre-defined TOCALL's are nice, but they are
> not a network standard either.

They're "standard" in the sense of being defined by the APRS standard; 
at that network layer they're an optional standard. Again, if you don't 
*want* to participate in APRS networking, I can't think of any reason 
why reason why you need to follow APRS conventions.  

> OK, for most folks the TOCALL address is not a big deal.  But it is
> very important to APRS.  You have made excellent use of the
> TOCALLs... for the APRS network, not an open network.

At the AX.25 layer they are tactical callsigns. At the APRS layer they 
have a more precice significance. 

And again, you're just mudslinging at APRS for not meeting your 
definition of "open". In networking technology, the term "open" means 
"operating by published rules" (like HTML, RFC822, and yes, AX.25), not 
"everything is format-free". 

Nevertheless, nobody's holding a gun to your head and saying you must 
use APRS formats..unless you want to talk to a station that is designed 
to use APRS...like a Kenwood with a native TNC.    

> If it were not a "problem" (for the Kenwood users)... then you would
> not be asking the world to change the way they configure their TNC's.

The Kenwood radios use APRS formats at that layer of the stack. If you 
don't care what they do with your packets, go ahead and ignore APRS 
formats. But if you *want* to talk to a station that is using APRS 
formats, it makes sense to me that you're going to have to play by APRS 

> but if your users set the path like U CQ V NOCALL,GG##GG,RELAY,WIDE
> --- then this will fail when they get back on the APRS network and
> not be digipeated.

I don't think there's any intention of further digi hops after a packet 
is heard on the ISS downlink by an earthstation, so what the subsequent 
path tokens are isn't really important as routing instructions. 

> Oops, APRS'ers won't set up that way, will they?  They transmit that
> big long LAT and LON position in the data part of the packet.

The "big" posit can be compressed...but then of course some people will 
whine that they can't "enjoy that content". :-) 

At the moment, even though I *could*, I don't happen to use my APRS 
software to control my ARISS traffic. But I do quite often use 
APRS-formatted packets for conciceness and compatibility.I keep a handy 
supply of prebuilt packets standing by in macros. 

There's absolutely nothing in my traffic that should cause anyone any 
problems interpreting my signals, and this practice is every bit as 
"open" as using a Q-signals within CW traffic. Even so, the cops won't 
come and bust me if I should send PSE SLO DN instead of PSE QRS. 
 73 de Maggie K3XS

-----/___.   _)   Margaret Stephanie Leber    / "The art of progress  /
----/(, /|  /| http://voicenet.com/~maggie   / consists of preserving/
---/   / | / |  _   _   _    `  _AOPA 925383/ order amid change and /
--/ ) /  |/  |_(_(_(_/_(_/__(__(/_  FN20hd / change amid order."   /
-/ (_/   '  K3XS  .-/ .-/    ARRL 39280   /___ --A.N.Whitehead ___/
/____ICQ 7161096_(_/_(_/__AMSAT 32844____/ <maggie@voicenet.com>

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