806 behind a DSL modem!

[mparry]

Any clarification on the following would be much appreciated...

Basically I am trying to use a Cisco 806 broadband router to provide multi-user internet access whilst also combining security features. Our ISP is providing a DSL line with modem / router - which I believe I can plug the 806 into.

Question(s):

1) Is it best to leave the ISP router transparent (i.e. setup no NAT / DHCP etc) so that 806 performs these functions?

2) If our network already has a DHCP service running (we're currently an NT4 network) is there any need to have the 806 perform this function.

3) I intend to use NAT on the 806 - however our internal address range is 192.1.1.x Can this cause problems due to the fact that it's not a correct private address range (e.g. 192.168.0.1)

Thanks for any help.

Marcus

 

[LoopyLoo]

I have just completed almost the same thing except using a netscreen firewall behind the DSL router. Concept is the same though.

1. No NAT on the DSL Modem - totally transparent.
2. Don't get the 806 to do DHCP - stick with what you have got.
3. Ugh! NAT is fine. You will deny your hosts access to anything on the 192.1.1.0/24 public space but it probably is not a big deal. Now might be a good time to change over to 192.168.1.0/24?

Hope it helps!

 

[mparry]

Cheers... Loopy Loo

I might well change my IP address range to 192.168.1.0/24 then. It shouldn't cause too much trouble I'm hoping.

Thanks again.

Marcus