[aprssig] distributed aprs visualization possible ?

Steve Dimse steve at dimse.com
Sun Aug 10 12:23:13 EDT 2008

On Aug 10, 2008, at 11:27 AM, Michael Conrad wrote:
> @Steve: Do you have some statistics, how often a specific function  
> (position report, wx report, history, ...) is used on
> findu ?

The top two are find and wxpage. Last month, find.cgi was hit  
16,243,193 times and wxpage.cgi was hit 12,455,837 times.
> I think the most used function today is something like: what is the  
> current position/status
> of station X and which other stations are nearby of station X.

near.cgi was hit 862,340 times, less than a tenth as much as the  
weather page. Weather is as important as position to my users, and  
near only 5% as important (by volume).
> Therefore the primary function of a (distributed) aprs visualization  
> is a realtime
> overview of the status of a given station and information in an area  
> of interest around this station.

Also, track.cgi comes in right below near, at 751,184 hits.
>> How are you going to show month+ long tracks?
> in best case not at all ;-)
> For a long term storage, you need more storage and better  
> replication. Eventually this can be added later,
> but for the first step a short-term visualization should be enough  
> challenging.

If that is your plan, OK. I see you have already changed the title of  
the message to reflect this is not about a distributed findU. Thanks,  
I appreciate that.

> What such a system should provide: distributed short-term  
> visualisation of aprs traffic (position, status, nearby stations)
Doing this as a distributed system is total overkill. It would take a  
couple days to write a Perl (or other high level language that  
includes web server libraries) program to parse just the position and  
status out of the stream and hold it an array in memory, and serve   
near.cgi and find.cgi type pages. Any surplus pentium would be able to  
serve tens if not hundreds of thousands of these pages a day. If you  
didn't have to deal with the obtuse APRS data formats like Mic-E and  
base 91 this would be a one day computer science homework project.

And, before someone says it, WinAPRS, xastir, APRS-SA, and UI-View  
(and probably others) already do something very similar, and have for  
many years...

Steve K4HG

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