Help with Very Simple 1721/ADSL Setup Needed

[anthonym]

Hi,

Our ADSL is moving to a wiresonly service, so I have bought a 1721 with 1ADSL WIC, I have been given the following details from the ISP:

VPI: 0

VCI: 38

Protocol: PPPoA

Modulation Type: vcmux

Auth Type: Chap

and a username and password.

How do I set up the router to connect?

[gpulos · Accepted solution]

this should be pretty basic for you if you're familiar with IOS and DSL a bit.

see this link for configuring ADSL WIC on 1700 using PPPoA w/CHAP:

http://www.cisco.com/en/US/tech/tk175/tk15/technologies_configuration_example09186a0080093e64.shtml

(this example shows two sides to the connection; you need to focus on the 1700/ATM side of the configuration, pointing to the dslam)

[anthonym]

Two rather big Ifs I am afraid! At the moment I am not either.

I will look at the link and may have some more quiestions later.

Thanks

[anthonym]

That seems to have worked. Once the router powers on, I can ping an address on the internet from the router.

Now I just need to get the PIX506E that sits behind it reconfigured.

Am I correct in thinking that the PIX default route will need to be the address of the FastEthernet0 interface on the router? If so, should that interface be a public or private address preferably?

[gpulos]

just to make sure i have your topology correct:

pix506 >>> dslRouter >>> ISP (internet)

if this is correct, then your pix506 defaultRoute will be the dslRouter FE0 as you've mentioned.

if you have networks inside that the pix does not know about, don't for get to add those routes to the pix.

i would think that the dsl routers ethernet interface can be private if the DSL/ATM interface has a public IP that can be NATed too.

[anthonym]

That looks correct, or with more detail.

Internal Network --->Pix506E--->1721 FE0--->1721 ADSL WIC--->Internet

The internal network is 192.168.93.0/24.

the ADSL WIC has a public address and we have 4 more public addresses available.

The current router in use only has one IP so currently the PIX has a private address on the inside, and a public on the outside, and does NAT for the internal network, with a default route of the router IP.

Ideally I would be able to use the public addresses inside, also via the PIX so that all traffic would go through the PIX, but only the internal subnet was NATed.

Internal |

--->Pix--->1721--->Internet

Public |