[Astlinux-users] Connecting topology

[Phil M. <ph...@mc...>]

Happy New Year everybody, and thanks for all your replies to my earlier =
query on this subject on the old mailing list.=20
=20
I've held off replying while I did a bit more research about using =
astlinux as a router, to avoid making a complete fool of myself in =
public. But I still don't understand it all, so here goes anyway. :-)
=20
I've got no problem with throttling my external connection to 90% of the =
available bandwidth to avoid queueing problems. Obviously it would be =
nice to have a system that copes with congestion without configuration, =
but I can live with it.=20
=20
I've discovered elsewhere that the net4801 won't cope with 100 Mbit/s =
ethernet routing (between PCs on my SoHo LAN) but should cope with my 4 =
Mbit/s internet connection OK. This is as I suspected, although it does =
make me wonder why my (much cheaper!) Netgear router copes with it all =
right - presumably it contains special hardware. This in turn makes me =
wonder whether the net4801 was a good choice of hardware for this sort =
of thing. Anyway, I think I can avoid all the speed problems by simply =
connecting my Netgear router downstream from the astlinux box, with my =
PCs connected to the router and my phones to the astlinux box. It's =
twice as much cable but what the heck.

I'm a bit puzzled that PBX-only mode is now the default, since that =
implies no traffic shaping, which I would have thought would guarantee =
problems whenever a big download or upload was in progress. What do =
people do in this situation? Use a separate internet connection? Or a =
clever router?

Anyway, I now want to enable the other ethernet ports on my box, and =
it's not obvious how to do this from reading rc.conf. My net4801 has =
seven ports (which now looks like a mistake). Assuming I was happy with =
slower speeds I still don't see how I can configure the unit to connect =
several phones or PCs to it. Is there a hidden assumption here that I'm =
missing, that an external router is always used? In PBX-only mode the =
phones connect to the EXTERNAL interface (the only one active by =
default), right? So the asterisk box is just another device on the =
internal LAN, rather than being physically connected between the phones =
and the external internet as I had assumed. If so, then I think I need =
to buy yet another router. :-(

I hope this is all clear. Maybe a couple of diagrams would help:

1. This is how I originally expected to connect things:
            __________          =20
           |          |----IP Phone
INTERNET---| astlinux |----IP Phone ...
           |    box   |----Computer
           |__________|----Computer ...

2. I now think PBX-only mode is meant to be connected like this:
            ________
           | Router |----IP Phone
           |        |----IP Phone ...
INTERNET---|        |    __________
           |        |---| astlinux |
           |        |   |    box   |
           |________|   |__________|

3. And this is how I now think the PCs should be connected:
            ________
           | Router |----IP Phone
           |        |----IP Phone
INTERNET---|        |    __________      ________
           |        |---| astlinux |----| Fast   |----Computer
           |        |   |    box   |    | Router |----Computer ...
           |________|   |__________|    |________|

Does that make sense?

--
Phil McKerracher
www.mckerracher.net