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A question regarding 857/877 and ADSL / Firewall setup

Hi all.

I will shortly be getting an 857/877 ADSL router and have a few questions regarding the setup with my infrastructure.

I have 10 static IP's from my ISP. 1 is for the WAN on the ADSL router, 1 is used for the external I/F of my Checkpoint. I have a DMZ with a web server and mail server. The DMZ / internal machines are connected to a managed VLAN capable switch with no routing between them.

Example:

WAN IP: 82.33.104.102

External I/F on Checkpoint: 82.33.104.103

DMZ I/F on Checkpoint: 192.168.1.250

Internal I/F on Checkpoint: 10.0.10.250

I should be able to just hook up my 877 to the external facing I/F on my Checkpoint right and let it handle the traffic that way? Any special config or routing I need?

Any problems do you think with this kind of setup? (I intend to do all firewalling via the Checkpoint).

Any help would be very much appreciated.

Thanks.

1 REPLY

Re: A question regarding 857/877 and ADSL / Firewall setup

When you mean wan ip - 82.33.104.102, that should be the dsl interface ip that you configure on the 857/877 router, correct ? This subnet cannot be again assigned to the lan side of the 877 router which inturn connects to the Checkpoint firewall. You will need to subnet this to a smaller subnet to allocate one on the wan side and another on the lan side.

Considering 10 addresses are given to you, i assume the mask is a /28 (255.255.255.240). Can you get me the first and last address in the subnet. Also the default gateway (Which is your ISP - is it 82.33.104.101 ?)

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