[aprssig] New Digi Settings
Henk de Groot
henk.de.groot at hetnet.nl
Sat Jun 11 14:50:31 EDT 2005
AE5PL Lists schreef:
> Henk has indicated to me that he is working on putting one together. I
> don't know the status.
Well, I would try to put a sample toghether if I have some time... Up to
now I did not get arround to do it up to now...
From the requirements in the NSR document I can tell you how to make the
rules for a DIGI_NED.INI file:
-------------------------------------------------------------------------
1. The digipeater repeats any packets it sees from a station on its "must
digipeat" list. This allows specific remote stations to make it into the
"metro" LAN as deemed proper by the digipeater sysop. The digipeater will
modify the path by simply appending its call with the H-bit set after the
“ok” list digipeater call plus any path defined by the sysop.
-------------------------------------------------------------------------
The above requires a rule that looks at the source call of a packet.
Something like "digifrom:" which looks like "digito:" but uses the source
call instead. So 1) can't be done except when adding a little code (it is
open source code...).
-------------------------------------------------------------------------
2. The digipeater repeats everything it sees directly (no digipeated
packets), stripping the entire path away and replacing it with just the
digipeater's callsign with the H-bit set plus any path defined by the sysop.
-------------------------------------------------------------------------
This can be done by "digifirst:". That rule only looks for calls that
appear first in the digipeater list; so when the packet has not been
digipeated before. Also packets with no calls in the VIA list are direct,
the can be handled with "digito:".
digifirst: all * all replace DIGI_CALL,WIDE2-2
digito: 1 * all 0 add DIGI_CALL,WIDE2-2
-------------------------------------------------------------------------
3. The digipeater repeats any packets it sees digipeated by digipeaters on
its "ok" list. This allows remote areas to make it into the "metro" LAN
as deemed proper by the digipeater sysop. The digipeater will modify the
path by simply appending its call with the H-bit set after the “ok” list
digipeater call plus any path defined by the sysop.
RELAY can be on the "ok" list allowing people to set up low-level RELAY
alias digipeaters. Packets with RELAY in the path would only be
digipeated if RELAY is in the first position and no place else.
-------------------------------------------------------------------------
This can be done with the "digiend:" rule which picks up packets that
"ended" with a specific call. You can add one rule with a list or multiple
rules. Doesn't matter. So
digiend: all pi1apa,pi1apk all add DIGI_CALL
or
digiend: all pi1apa all add DIGI_CALL
digiend: all pi1apk all add DIGI_CALL
do the same thing.
-------------------------------------------------------------------------
4. The digipeater does full dupe checking (CRC or checksum) based on from
call, unproto, I field length, I field data. The digipeater will not
digipeat any packet where its callsign appears before or including the
call with the H-bit set in the path. The depth of this dupe check would
only need to be about 30 packets long.
-------------------------------------------------------------------------
DIGI_NED already has that, except that it can be refined a bit by inluding
the destination call in the check (called "unproto" in the text).
I've put a sample "digi_nsr.ini" at my website
"http://www.homepages.hetnet.nl/~pe1dnn". It is experimental so
improvements are welcome.
Kind regards,
Henk.
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