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New Member

Newbie: questions about bridged ADSL

I have to configure my 870 router for bridged ADSL. I managed to configure it for pure bridging, but I would like to use IRB. This implies that I should improve my knowledge of IOS. I looked at this article:

I tried to follow it, but I'm having some problems. Before I start posting my configuration (actually I tried a few :-)) I have a couple of questions i would like to ask:

1) I don't have an ethernet interface. I could use fastethernet, but that would make my internet connection available only to the single fast ethernet. Is it a good idea to use vlan1? Should I use then a BVI? How should I configure the NAT in that case? Shouldn't the inside be on vlan1 and the outside on atm0?

2) the article says that I have to configure the mac address of bvi1, setting it to the mac address of... bvi1? And all of this while creating it?


  • WAN Routing and Switching

Re: Newbie: questions about bridged ADSL

Please give the following information:

1. Is your DSL service DMT based?

2. Is your ISP using a Cisco Systems DSLAM?

3. What pins on your wall jack have been activated for DSL service?

Try the following URL:

New Member

Re: Newbie: questions about bridged ADSL

thank you, I finally managed to make it work.

atm 0.1 has to be in bridge group 1 (ieee spanning and ip routing), with a dhcp ip address. bvi 1 will also have a dhcp ip address. And then I have vlan 1 with an ip address of vlan 1 is on the nat inside, bvi 1 on the nat outside.

My only problem now is that every time I reboot the router I get a message saying that a random mac address has been chosen for the bvi in bridge group 1 since there is no mac address associated with the selected interface. Not a big deal, but I would still like to fix it. Maybe I'll start a separate thread.

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