[Testing] os240py - collaboration over wireless

James Cameron quozl at laptop.org
Mon May 31 22:29:21 EDT 2010

On Mon, May 31, 2010 at 08:59:49PM -0500, Mikus Grinbergs wrote:
> The answer I got was that the "presence detection" (or something)
> capability used multicast, rather than depending upon "standard"
> interface defined IP-addresses.

I've just booted one laptop on os240py to use mesh, but with packet
capturing on one that was already booted.  The captured packets were
interesting.  After the booting laptop established an IP address, there
was a multicast DNS exchange, followed by an explicit connection to the
presence service on TCP port 5298 on the already booted laptop.

> What I noticed with os240py was that as soon as both system had
> connected to the same wireless Mesh channel, each saw the other (i.e.,
> Neighborhood View at both systems showed the icons for both systems).

I see that too.

> Are you saying that the multicast capability that was explained to me
> months ago was NOT active in os240py with only Mesh connected ?

Yes, you can verify this by using "ip route list", and on os240py there
is no multicast route, but in the same network configuration on os802
there is.

> [ Is there a command that I can manually enter at a Mesh-connected
> os240py system to activate such a 'default multicast route' ? ]

The "ip route add" command I gave will do this.  The "ip route list"
command will show the change.

James Cameron

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