[LUNI] Linksys routers/switches and Comcast Cable

[Andrew Close]

On Mon, 28 Mar 2005 10:46:05 -0600, Stef <stefmit at gmail.com> wrote:
> Plug the cable modem Ethernet interface into a hub or one of those
> cheap (e.g. Netgear) switches, which behave like hubs for ports
> matching speed and duplex, and then plug into one of the ports your
> router (I am not sure I understand what you're doing with routerS),
> and into another port your linux box (make sure you match the port
> speed as the router eth interfacee, to be able to sniff), running
> (t)ethereal. Take a look at what's going on, and you'll see what
> you'll need to do next.

good idea Stef.  i didn't even think to try ethereal.  i don't have a
lot of experience with it, but it is kinda fun to see what's going on.
 i'll give this a shot and see if i can see what, if any, traffic is
going on between my router and the modem.

as far as multiple routers, i'm not doing anything special with them. 
aside from the one that connects to the cable modem, i'm using them as
glorified hubs.  the first was a quick and easy firewall so i could
have multiple machines gain access to the net without having to be
completely paranoid about getting hacked.  the second was the WRT54G
because i wanted wireless once i bought the PowerBook.  the third was
part of the package deal with Vonage for VOIP.  so the first router
was setup with an internal IP of 192.168.10.1 and was a DHCP server. 
the other two were just devices hooked to the first and had their DHCP
servers shut off.  once i get things working as they were i plan on
pulling the BEFSR41 out of the mix as i don't currently have enough
machines to need the extra ports.

so a rough ascii schema of my network looked like this:

internet
    |
Linksys BEFSR41
   |                           |                               |
Linksys Vonage    Linksys WRT54G       two macs
  |                            |
Phone                  PowerBook

the BEFSR41 was set up to obtain it's IP automatically from the cable
modem.  it then had an internal IP of 192.168.10.1 and also acted as a
DHCP server to the rest of the network.  the Vonage router is the
newest addition and is only used for the phone.  it obtains it's IP
from the BEFSR41's DHCP server and has no clients of its own.  the
WRT54G obtains its IP from the BEFSR41's DHCP server and has it's own
DHCP server turned off.  it's just being used as a bridge i guess,
since my PB was getting its IP from the BEFSR41's DHCP server as well.
 since this solution worked in the office upstairs, i set it up like
this downstairs...