[aprssig] IGate Registering for ANSRVR (Messaging failures)

Steve Dimse steve at dimse.com
Fri Jul 15 13:18:48 EDT 2016

> On Jul 15, 2016, at 12:55 PM, Pete Loveall AE5PL Lists via aprssig <aprssig at tapr.org> wrote:
> Whoever came up with the "receive-only" IGate as a good thing did not think through that APRS is a -communications- protocol, not a tracking protocol and they did not fully understand the potential for breaking the communication mechanisms that APRS-IS depends on.
I came up with it, and I did think it through.

First of all, satellite IGates should be receive only, they cause QRM otherwise.

Second, there are two different uses for the APRS-IS. The first is to get RF packets to the internet. This came first, and numerically is responsible for a far greater percentage of the use of the APRS-IS. Two way messaging is the other use, and one-way IGates are indeed not useful for this purpose. However they do not break the communications mechanisms. The only potential adverse effect is that someone considering installing a two way IGate in an area already served by a one-way might not realize their service would still be valuable (since local stations already appear on the APRS-IS), and not set up the needed service.
> Why not configure your home station for direct-only bidirectional and then you can support messaging instead of only sometimes being able to communicate reliably?
It is interesting that this suggestion still runs afoul of the one reason I give above why one way IGates may hurt the functioning of the system. A ham wanting to set up a full, multi-hop two way gate might be discouraged by a zero hop IGate, since all the traffic, regardless of number of hops, is sent to the APRS IS.

Third, I have always believed strongly, and acted on the belief, that the choice of what goes on a local RF network is the choice of the local hams and must not be dictated by any national or international group no matter how well-intentioned. If a local area decides for any reason it does not want 2-way messaging on its network it should not then be forced to remove all its traffic from the APRS IS.

Fourth, IGates are illegal or require special permissions in some countries. We should not exclude people who live under less enlightened rules from placing their traffic onto the APRS IS if the rules allow RF to INet but not the reverse.

Fifth, and very importantly, is the risking of our ham licenses. The deliberately weak authentication mechanism built into the APRS IS was designed only to provide cover for IGate operators from FCC rules. Once that mechanism was published by aprsd in the name of open-source purism that cover evaporated. Every IGate operator puts their license at risk by opening a two-way IGate. The risk is small, but again, the only alternative should not be non-participation.

Steve K4HG

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