Topic: Placing router between modem and SME while maintaing server/gateway functions

[gabby]

Hi all,

I have searched high and low on the forums for topics to answer my question. I found a few that seemed peripherally related, but none that answered my questions directly. Perhaps someone can either answer my question and/or point me at a post that addresses my questions.

My Current Network Topology
CABLE MODEM -------SME Server (DHCP)--------Wireless Router--------Wireless Devices
                                                                            |
                                                                            ------------------Wired Devices
SME Server is in Server/Gateway mode serving web and mail to several remote networks nationwide.

My (New) Desired Network Topology
CABLE MODEM---------Router (DHCP)-------SME Server (DHCP--------Wireless Router---------Internal Wireless Devices
                                         |                                                                   |
                                         |                                                                   -----------------Internal Wired Devices
                                         --------------External Wired Devices (Entertainment System)
                                         |
                                         --------------External Wireless Devices (Guest/Public Network)
SME Server should continue serving web/email as in Current Network Topology
External router will be configured to serve IP addresses in 10.11.1.x subnet.
Internal router will be configured to serve IP addresses in 192.168.1.x subnet.

I am using DynDNS for DNS services and NoIP.com for mail port forwarding services (my local ISP blocks standard email ports)

I am not interested in firewall capabilities on the external Router. I simply am looking to reduce latency to the entertainment devices in my network.

Since I am serving up web content that is critical to some organizations operation right now, I can't afford to bring the network down to figure this out by trial and error.

My questions are:
1. How do I configure the external router (Netgear WNDR3700v4) to function as DHCP for downstream devices and still allow SME to serve web and email content as it does today?
2. How do I configure SME server in the new topology so that the services it provides today continue making the network changes transparent?

I'm concerned about HTTP/HTTPS, POPS3, port forwarding, DynDNS, NoIP, etc.

I appreciate any assistance you can provide.

Best regards,

James

[mmccarn]

Your configuration is much simpler if you use an access point on the SME LAN interface instead of another router:

CABLE MODEM---------Router (DHCP)-------SME Server (DHCP)--------Switch---------Wireless Access Point ------Internal Wireless Devices
                       |                                            |
                       |                                             -----------------Internal Wired Devices
                        --------------External Wired Devices (Entertainment System)
                       |
                        --------------External Wireless Devices (Guest/Public Network)



1. Set the SME WAN interface to a fixed IP  that is outside the DHCP range served by the WNDR3700.

2. Configure port forwarding in the WNDR3700 to send everything important to the SME, or set the SME as the "DMZ" host on the WNDR3700.

3. (not asked) - if you access the SME by *name* from the LAN, you should check to make sure that the LAN workstations are using the LAN IP of the SME server.  With the SME on the internet, you could  serve websites using remote DNS to the LAN clients by way of the WAN IP, which wouldn't work any more once the WAN IP is moved to the WNDR3700.

4. (not asked) - access to SME servers from the 'External Wireless Devices' and the 'External Wired Devices' may be problematic -- if their DNS gives them the WAN IP for the SME they'll be looking for SME services on the WNDR3700; if their DNS gives them the LAN IP for the SME you'll have to add the 'External...' network as a 'Local' network on the SME server.