[nos-bbs] Re: AXUDP and APRS

maiko at pcs.mb.ca maiko at pcs.mb.ca
Tue Apr 12 21:50:15 EDT 2005

> This is way too hard.

You mean linking axudp between JNOS and *some application* on
the linux side ? Not really ! I have JNOS and Baycom's BCM 1.42n
running on the same Linux box, linked via AXUDP.

JNOS is networked to Linux using the TUN interface. The JNOS side
is, the Linux side is See my example
autoexec.nos on my site.

On the JNOS side, I simply do this :

  attach axudp bcm 256 BCM 95 95
  ifconfig bcm description "link to my bbs (mailbox)"

Note the IP address is pointing to the linux side of the TUN
interface. The BCM application has a similar type of attach to (JNOS). NOTE: I do not use the default AXUDP port,
I chose UDP port 95 instead, due to some internal conflicts
with the way I use UDP on my system.

The key thing here is that ANY ip application running on the
Linux side will be BOUND (BIND) to the IP address of the Linux
interface it uses to get to it's destination. In this case, the
BCM needs to get to JNOS, so it will take on a source ip address
of the linux side of the TUN interface, not the ETH interface,
or any other interface you have running.

> In APRS, you can "telnet rotate.aprs.net 14501" and be
> receiving data.  Add a simple password to that and you're
> part of the system.

You mean the APRS internet feed (port 1314 for example). I
thought 14501 was a status page. Anyways, no big deal.

> Why can't we have something like:
>   "attach virtual-asy rotate.ampr2.net callsign <password>"

Are you suggesting that a *central* server accept requests
for AXUDP or AXIP tunnels ? In practice, it's very easy to
do. As a matter of fact, in NOS it only requires the removal
of a couple of lines of code to have NOS blindly accept AXUDP
or AXIP from any source. Putting in some type of validation
would be a bit of extra work.

Gosh, you know, this is soooo funny that this is being talked
about. Seems to me that Barry (K2MF) and myself, and perhaps
even Brian (N1URO) had a chat about something like this not
too far back ago, I just can't remember exactly what it
was we were talking about ...

Guess it wasn't that important then, ha ha ha ...

Hey Barry or Brian, how about a comment ?

Maiko Langelaar / VE4KLM

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