Since it was decided that it is legal for amateurs to use the internet
for messaging to and from RF, a broad range of uses have been implemented.
BBS ipip tunneling to and from the amateur radio 44.x.x.x network, NTS
messaging services to and from the internet amateur network, and of course
APRS routing to and from the internet. There are more usages, but what
we are most interested in here of course is using the internet to expand
the APRS network.
I will not go into much detail of how IGATES work here. There is no
need for an operator to know all the gory details of how IGATES work. It
is more important for the operator to how to utilize them.
Using the internet, we can now expand the APRS network world wide! This
is transparent to the user and no special routing needs to be setup. If
your signal is heard by an IGATE then that IGATE will automatically relay
your packet to the appropriate station through the internet.
This has many advantages that may not be readily apparent. Now the local
APRS networks can be tied together from city to city without having to
use unreliable and QRM causing RF paths. Speed is also another great advantage.
Imagine trying to talk to someone coast to coast through 1200 baud rf modems
relying on who knows how many digis! As well, there is no need for an operator
to know the path to the receiving station. The packet will be routed to
the receiving station with no prior knowledge of how it is going to travel
to it's destination.
If there is an IGATE in your area, your posit information will automatically
be routed to the internet as well, and then will be distributed throughout
the network and your station will be seen world wide! As you can see, it
is no longer necessary to use unreasonably long unproto paths just to be
seen outside your local area.
Another advantage of IGATES is for amateurs that do not have the resources
to set up an APRS station. By using an APRS program that allows the user
to connect to the internet (most all do these days), the amateur has all
the capabilities of the APRS network without having the expenditure of
a radio and TNC!
As stated earlier, the IGATES operate transparently to the operator.
However, if your station is on the fringes of the local APRS network, you
may need to specify the callsign of the IGATE you wish to use as the last
station in your unproto path. This will insure the routing back to you
in those cases where you are forced to use many digis to get to it. As
large as the APRS network has grown in recent days, this will only be necessary
in special cases.
Remember, do not take it upon yourself to set up an IGATE
in your area without first talking to your local APRS group and finding
out if one is necessary. Since IGATES relay what ever they hear to the
internet, more then one in any given area will cause "internet QRM". Most
APRS programs allow you to gateway RF<>internet, do not turn
that feature on unless there are no IGATES in your area and you are the
only one in the area doing it! This is very important, you can imagine
what problems will arise when more then one station is gating the same
information to the internet. Also, it is important that IGATES just as
digis be "on the air" 24/7. Neither is of much use otherwise.
When setting up your unproto paths, remember it is much more beneficial
to be able to hit a digi that hears an IGATE then to hit a digi a hundred
miles away.
Again, be responsible in setting up your APRS station. Cooperation and
conforming to established usage for your area will ensure that the APRS
network will be reliable and useful now and into the future as it grows.
Next:
Explanation of APRS Protocols - coming soon?
Jump to:
APRS Facts and Myths
Explanation of APRS Protocols - coming soon?
Conclusion - coming soon?