Well, in case anyone's interested, I did get mrouted to compile
okay. There are binaries on my website at ke6i.com in the
pub directory in case anyone is interested. The trick to compiling
mrouted 3.9, is that there are instructions on the web -- which say
they are for Red5.1. Well, following these instructions to a T,
also allows me to build mrouted on Red6.1.
I setup one machine, with 2 networks. That is an ethernet network
and an ax25 network. With multiple computers on the ethernet
side, and two machines that is the Linux box, and a PC running
sv2agw on the AX25 side.
mrouted had no trouble routing packets from the ax25 side to the
ethernet side. I wrote a little test program for multicast -- based on
examples on the microsoft website, and I was able to send multicast
packets on the AX25 network, and have them pop up on the ethernet
side.
However, packets from ethernet to ax25 didn't get routed. I'm not sure
yet what the issue is here. To the credit of the sv2agw software, when
I run the receive program, I do see a packet go out that I assume
is the IGMP packet telling the host that it wants to receive that
appropriate
'MEMBERSHIP' I think is the appropriate term. But
somewhere, I guess this gets lost because I never see the packets that
are on the ethernet come back out over ax25. Sigh. I can see the
inforation that the receiver is ready come in with the 'listen' command,
but then the receive side never sees the data.
I'd also say that the broadcast rate on mrouted is a little too frequent for
ham radio packet link -- that is being at 2 minutes, but this is
easy to change in the '.h' file.
Also, I'd say that the programming interface for multicast is pretty
amazing.
And that if this could work, then something like maybe a chat system could
be done without any servers or anything. (Though maybe some FEC would
be needed to make sure all the input gets through.) And all those sticky
issues could be passed down to the OS, where they should be, by gum. So,
if it ever works, I think it'd be worth it to try to set up some tunnels, if
anyone else
is interested in this.
Anyway, at this point, I'm not sure if the issue is in the kernel or in
mrouted,
or perhaps in some kind of config screw up by me. In the current 2.2.12,
turning on and off multicast works fine for ax25 or ethernet. I guess it's
only turning
off and on broadcast that's broken. If anyone wants to see
any of the test code I'm using to check multicast (Mostly windows code.)
send
me an email, and I'll pop the files on ftp://ke6i.com
