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HI all,

I am trying to figure out a solution where I need to Do some bridging for several xDSL customers.

We have a ppp tunnel coming in on our g0/3 interface that are coming from our providers POP router

This is a L2TP tunnel. This is the setup :

CPE----PPoA-----Dslam----POP--------------------POP-----------------Our router-----------Internet


The users at the CPE device is setting ip a PPP tunnel for authentication against radius.. Both are the POP location and

our location. Then a L2TP tunnel is formed from incoming POP (LAC) to our (LNS) router…

On the LNS I am configuring this :

Interface g0/3

Ip address

Vlan-range dotq 1 2

Bridge-group 6

Vlan-range dotq 3 4

Bridge-group 7

Interface BVI 6

Ip address

Interface BVI 7

Ip address

I am not sure if this will work… It is not tested yet, but If on the incoming POP

I was able to tag the packets with a vlan tag, should this not be working smoothly??

ANY advice about this or other method to do this is very much apreaciated


Re: bridging/ppp

PPPoA was primarily implemented as part of ADSL. It relies on RFC 1483, operating in either LLC/SNAP or VC-Mux mode. The ATU-R encapsulates IP packets into PPP frames and then segments them into ATM cells via AAL5. The PPP link is terminated at the NRP and the originating workstation's IP packet is routed to its final destination through the service provider of choice.