[Xastir] ax.25

[Curt, WE7U]

On Wed, 21 Jul 2010, Jason KG4WSV wrote:

> If it's in a linux/xastir context, this frequently refers to the ax.25
> kernel support available in linux.  Since the ax.25 protocol _is_
> networking, some linux hams hacked out a network interface driver and
> added it to the kernel, where all network interfaces belong.  The
> result is that you can hit the network stack on a single interface
> (i.e. radio/TNC) from multiple applications and the kernel will handle
> things so that the applications don't step on each other.

Roger.  You also have to watch out for applications that send out
broadcasts or queries to ALL network interfaces, because as soon as
you implement an AX.25 kernel networking interface they'll start
talking out that interface too.  Samba will do this, but there are
others.  You can fix this with firewall settings or usually within
the individual app's configs.


> The other way to interface is the same way windows and macs do - the
> kernel provides a serial interface (RS232) to the TNC, and the
> application implements the entire ax.25 stack.  This makes it
> difficult to impossible to share a TNC among multiple applications.

We have a Soundcard HOWTO and an AX.25 HOWTO on the Xastir Wiki
pages, in case you decide to try one of those.

It is nice to be able to share a frequency among several apps.  I'm
running a TNC-X (KISS-only TNC) with AX.25 kernel networking at home
for Xastir and igating.  I could throw Digi_NED on there too if I
wanted full-fledged digipeating.  At the same time I could do a
telnet, ftp, or ssh session to others on RF.

-- 
Curt, WE7U.                         <http://www.eskimo.com/~archer>
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