[aprssig] Future Concept for APRS

[Bob Bruninga]

Again... these appear to be more examples of why I worry about individual sysops making draconian local hacks to the network:

> Network viability preservation says that 
> if you do send more than N messages
> per minute, we must not digipeat your packets.

What!  The person who gets involved in a situation, event, or emergency may need to send lots of messages right now!  Having such a draconian rule that limits an individuals need to communicate destroys the flexibility of APRS to be responsive to the need of the moment.  We need to be careful in making narrow definitions of what one individual wants to see on his screen.

If some people are overusing the network on a regular basis for idle chit-chat that is objectionable, then raise the issue with those individuals.  Dont cripple the network!

>  Not digipeating same packet heard from 
> another local digi a few seconds before 
> (viscous digipeating) is also a viability 
> preservation issue. 

And it can also be a network BOMB tha can cripple it under some very frequent conditios!  Many digis that are situated between two other digis will MOST OF THE TIME not hear the packet digipeated!  This is a very common occurence.  If you implement this simplistic viscous digipeating without thoroughly thinking it all the way through, you will reduce by 50% or more your network throughput for each digi where you implement this.  This could RUIN the network!

Please, understand that APRS digis RARELY hear every packet, because FM collisions occur MOST OF THE TIME.  Hence, Viscous digipeating is a BAD idea, because it multiples the number of SLOTS taken by each packet, instead of having ALL digipeaters respond at the same time which is the way APRS was designed.
Viscous digipeating will really slow down a network and multiply QRM!

> Digipeating packets with indicated position 
> far from local system is also very questionable.

It happens very often for the travler with his HT.  When I travel and pass through airports with my APRS HT, I frequently use it to send messages and I do NOT usually bother with the GPS (doesnt work indoors anyway).  Therefore the radio is probalby sending my HOME location, even though I am 500 miles away.  If you implemented this rule, no one could message unless they had a GPS!  And that is a severe restriction to the messaging function of APRS...

> When a chap in south Sweden sends a 
> beacon of WIDE7-7, and I hear it repeated 
> 5 to 10 times in Helsinki, it means that  
> a) there is 2m tropo in baltic!   
> b) bloody flools really should know 
> better and not do that kind of thing

Yes, and the New-N  Paradigm should limit hops to 2 or 3 and is a perfect solution.  No need to criple the network when the network already has the tools to solve the problem to limit large hop counts.  Also you should educate the user that 7-7 is abusive.

> So, if here somebody wants to use 
> messaging with somebody, they are within
> the service area of same digipeater.  
> No non-local traffic.

This is too bad that Finland has hacked up the APRS network and does not  allow two-way messaging.  This is a shock to me and to all APRS travelers!  And it shows why messaging does not work well via Igates beacuse of such local draconian hacks... that destroy the integrity of the APRS network and Global APRS-IS connectivity!

> If you transmit positionless packets, 
> in our thinking they will not be
> digipeated unless you have recently 
> enough sent a position that is within
> our local service coverage.

So APRS in your area is only for vehicle tracking.  That is unfortunate.  Vehicle tracking is not of much interest to most hams.  Most hams want to do 2-way communications, not watch some tracker drive around with no way to talk to him...

>>> Remember, it is our network, not yours. 

No, the network is supposed to serve ALL ham travelers, not just some locally defined only-do-it-our-way kingdoms.

> Here locally we have been hashing some 
> Requirement Specifications for an APRS 
> DIGI/IGATE as we see it.

I hope I can find the time to look at them.  So far, some of the ideas you have proposed are very worrysome to the consistent operation of the network for the traveler...

>  http://repo.ham.fi/svn/aprx/trunk/doc/

Please give the New-N paradigm and the ability to trap large N a good impementation.  I think it will solve many of your problems... if done correctly...

Bob, Wb4APR