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DHCP relay and DHCP server


Please visualize the following and suggesst me a solution.

1. I have PIX515E ,whose outside ethernet interface connected to ethernet interface of the Cisco 3745.

2.The Cisco 3745 has five E1 modules,out of which one E1 is connected to Internet,and other 4 E1s are connected to MPLS cloud.

3.Behind the firewall I have a DHCP server.

4.There are three remote locations,all are connected to MPLS cloud by means of E1.

5.Every remote site are equiped with 10 to 15 clients.

Now my requirement is as follows.

1. Every remote client has to get the IP address from the DHCP server which behind the PIX firewall at the main site.

2. All remote sites internet traffic has to go through the main sites PIX firewall.

Is this possible.

My assumptions are follows.

For the case 1. I can use the IP dhcp helper address command in the router and send all the UDP broad cast of remote clients to DHCP server,but the problem is PIX is placed between Router and DHCP server,How it is possible?

Case 2. All remote traffic can go to internet not through the PIX firewall,if it is required to pass through the PIX firewall either the ISP termination should be an ethernet then I can connect to PIX oudside interface,then it is possible,otherwise they have to have one more router which is connecting to Internet,then the ethernet interface of that router will be connected to PIX outside interface,then the inside interface of the PIX can be connected to ethernet interface of theCisco 3745,then this Cisco 3745 can be connected to MPLS VPN by means of 4 E1s,then it is possibe routing all the remote internet traffic through the PIX firewall.

Please suggest me for both requirement.

Thanks and Regards,


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