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<a class="moz-txt-link-abbreviated" href="mailto:n0yxv@gihams.org">n0yxv@gihams.org</a> wrote:
<blockquote cite="mid1121289300.42d5845448a88@www3.srcproductions.com" type="cite">
<pre wrap="">Can somebody point me toward the right web page to explain Directional SSID's,
or what ever they are called? I found it in a config file that looks like
below.
// Path used when SSID routing is used (Up to 8 hops)
// (Direction) Path
// xpath [path]
NorthPath =
SouthPath =
EastPath =
WestPath =
NorthPath =
SouthPath =
EastPath =
WestPath =
--
</pre>
</blockquote>
It's a feature of APRS intended to be a shortcut way for users to
express particular desired paths that never caught on. <br>
<br>
As a digipeater sysop, you would enter paths consisting of specific,
actual callsigns of digipeaters , located north, south, east or west
relative to your own digi, in your digipeater's software or firmware.
Users could then select this path (instead of generic paths like
WIDEn-N) by changing the SSID of the destination callsign in their
setups. This would allow the user to, for example, beacon "North up
the coast" without having beacons propagate inland or to the south,
without having to know the actual callsigns involved (the digi would
know them instead). . <br>
<br>
<br>
Quoting from the APRS 1.01 standards document, available from:<br>
<big> </big><font size="-1"><big><a class="moz-txt-link-freetext" href="ftp://ftp.tapr.org/aprssig/aprsspec/spec/aprs101/APRS101.pdf">ftp://ftp.tapr.org/aprssig/aprsspec/spec/aprs101/APRS101.pdf</a></big><b><br>
</b><big>or <br>
<big> </big></big></font><font size="-1"><font color="#008000"><big><font color="#000000"><a class="moz-txt-link-abbreviated" href="http://www.ui-view.org/files/APRS101.pdf">www.ui-view.org/files/APRS101.pdf</a> <br>
<br>
pages 25 and 26:<br>
<br>
"If the Destination Address SSID is non-zero, the packet follows one of
15<br>
generic APRS digipeater paths.<br>
<br>
The SSID field in the Destination Address is encoded as follows:
<br>
APRS Digipeater<br>
SSID Path<br>
<br>
-0 Use VIA path <br>
-1 WIDE1-1 <br>
-2 WIDE2-2 <br>
-3 WIDE3-3 <br>
-4 WIDE4-4 <br>
-5 WIDE5-5 <br>
-6 WIDE6-6<br>
-7 WIDE7-7 <br>
-8 North path<br>
-9 South path<br>
-10 East path<br>
-11 West path<br>
-12 North path + WIDE<br>
-13 South path + WIDE<br>
-14 East path + WIDE<br>
-15 West path + WIDE "<br>
<br>
In order for this to work, digipeater software or firmware had
explicitly support this kind of SSID routing. Most never did. <br>
<br>
1) Practically no one ever used this technique (particularly because
it isn't supported by the KPC3+ TNC used in such a large percentage of
all digipeaters).<br>
<br>
2) Plain WIDE-type paths defined in this standard, (as distinguished
from WIDEn-N paths) are now obsolete and being phased out. <br>
<br>
3) In today's crowded APRS environment, no one should be using ( or
facilitating the easy use of) paths with 4-7 hops in them.<br>
<br>
<br>
Best Suggestion: Just leave these items blank.<br>
<br>
For more information on APRS digipeating conventions and how they have
evolved and changed over the last few years, visit my web page at:<br>
<a class="moz-txt-link-freetext" href="http://webs.lanset.com/wa8lmf/DigiPaths">http://webs.lanset.com/wa8lmf/DigiPaths</a> <br>
<br>
<br>
<br>
<br>
Stephen H. Smith wa8lmf (at) aol.com <br>
<br>
Home Page: <a class="moz-txt-link-freetext" href="http://wa8lmf.com">http://wa8lmf.com</a><br>
<br>
New APRS Symbol Chart <br>
<a class="moz-txt-link-freetext" href="http://webs.lanset.com/wa8lmf/miscinfo/APRS_Symbol_Chart.pdf">http://webs.lanset.com/wa8lmf/miscinfo/APRS_Symbol_Chart.pdf</a> <br>
<br>
New/Updated "Rev G" APRS <a class="moz-txt-link-freetext" href="http://webs.lanset.com/wa8lmf/aprs">http://webs.lanset.com/wa8lmf/aprs</a><br>
Symbols Set for UI-View, <br>
UIpoint and APRSplus:<br>
<br>
<br>
<br>
<br>
<br>
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