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Thanks to someone on this site I was able to get the Serial0/0 interface up. I now have:

 DCD=up  DSR=up  DTR=up  RTS=up  CTS=up

My next challenge seems to be in the routing and/or PC ip setup.

This are the pertinent details from L3:

WAN Network: Level3 Side: Customer Side: Cust. LAN IPs:

What would be the IOS commands to setup this route correctly? Am I correct that I would the choose an IP like, subnet, gateway


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Joseph, I am assuming that you would like all your traffic to head up to the L3 network. So you would want to add a route statement in your router that would take any traffic and send it to the next hop (Level 3).

The route statement looks like this: ip route

I am assuming that you want to route traffic to client computer not NAT the workstations.

You should then have another interface that you can put the network on. Usually this is the ethernet interface that plugs into your local network switch. You would set the ip address to leaving 29 hosts for your network. The command that you run on the interface is: ip address

config t

interface serial 0/0
 description TO_LEVEL3
 ip address


ip route

interface fastethernet0/1
 description TO_PC_OR_LAN
 ip address
 no shutdown



To get a client connected you would then use an ip address in the range of the netmask would be and your default gateway would be

So the path of traffic would be: client pc ( -> router ethernet ( -> router serial ( -> L3 serial ( -> Internets

Hope that helps

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