aprsc - an APRS-IS server in C with filtered connection to the core servers

You're looking at the source code of aprsc, an open-source APRS-IS server. This Code was initially written by Hessu, OH7LZB. Upstream server connections in his work are not filterable. You always got the full APRS-IS stream (abt 19k/s).

Additionally some code was added by dgentges that made the upstream server-connection filterable.

Reasons to run APRSc on your local network

Maybe you have a direwolf setup running your 2m and/or 70cm APSR station. Ofcourse dirwolf needs a connection to the APRS-IS network to send/receive data from. Other devices, be it your LoRa-Gateway , the weather-station, the baloon-tracker, ... also require a connection to these servers. The same applies for your prefered user-program (xastir, UiView, ..)

So at the end you have a dedicated server-connection for any of these. Every connection produces (it may be very little) load on the APRS-IS core server that is connected to. In addition, if your internet (or 44.0.0.0/8) connection is lost, you are relatively blind.

Here comes a locally running instance of an "APRS-IS" server into play. The packages, that are included in some linux distros, request the full feed of the upstream server, that generate a constant datastream of about 19kB/s, which can exhaust your datavolume at some time. The additions of dgentges to the original APRSc code implement the ability to filter the upstream (to be precise, its the downstream) server connection with the well known serverside filter commands.

Running your own, local APRSc has the following advantages:

• never be blind when internet is down
• reduce the load on the core servers
• reduce the bandwith needed for APRS-data

Installation

cd ~
apt-get install build-essential autoconf make git vim libevent-dev -y
git clone https://github.com/ploeffler/aprsc
cd aprsc/src
./configure
make
sudo make install

This will install the entire server in /opt/aprsc. The config-file is in etc/.

Configuration

You will have to change these lines in the configuration:

ServerId   NOCALL
PassCode   0
MyAdmin    "My Name, MYCALL"
MyEmail    [email protected]
Uplink "Core filtered" full  tcp  rotate.aprs.net 14580 filter r/46.0/15.0/1000
MagicBadness	42.7

The magic trick is the following line:

Uplink "Core filtered" full  tcp  rotate.aprs.net 14580 filter r/46.0/15.0/1000

If you are not familiar with the use of server-side filters: please check this page

Be sure to remove the line:

MagicBadness	42.7

Docker

A dockerized version of this server is available at this repo

Have fun!

Peter, OE6PLD