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New Member

NATing and Bridging

Hi Expert,

I need to configure Cisco 877 router to run Bridging and NATing at the same time, could it be done?

The detail will be like this,

My router have 4 switch ports which I configure my port 1 to VLAN1 and port 2 to VLAN2, my WAN port is ADSL over POTS.

VLAN1 will be connected to my web server for public access, but I'm not configure static NAT, I need bridging to my WAN port, which mean my server will running public IP at same range with my WAN (PPPoA Static IP).

My VLAN2 will be configure NATing for all the clients to access internet, I need to configure PAT on my WAN IP to share internet connection for all the clients.

So my ideal will be configure BVI interface to bridge my ADSL dialer interface and VLAN1, then configure dynamic NAT inside on my VLAN2, NAT outside on my BVI interface.

Will this solution able to work on my Cisco 877 router?

Can anyone please advice?

Appreciate your all can help me.

Thank you.


Au Yeong Shaw Voel

New Member

Re: NATing and Bridging

Why not run your server on a private address i.e. 192.168.100.X and your clients on VLAN2 on 192.168.50.X, then statically NAT your server inbound/outbound with your clients overloaded? You can then create ACL's to stop any cross traffic on the internal VLAN's (if needed) and you would then offload any INET erroneous traffic (ping, trap, etc) into the router interface. Additionally, would create ACL;s that would only allow traffic to the server that was needed on a by port basis.