configure dsl connection through a modem + router configuration

Posted on 2011-10-20
Last Modified: 2012-05-12

Hi all,

Please can someone advise/help me -

I wish to replace my BT 2wire adsl modem/router device with a better model.
The present device has built in modem that connects dynamically and then allows me to configure my static IP block as an additional public network to be routed through to the lan ports.
This then shows traffic has coming and going from the staic IP.

Most hardware companies are now pushing a separate modem and then router solution to do this.

I am worried about using separate devices in case the static IP address is not used correctly (I have a mail server on it).

Would I configure the dsl modem to use a dynamic address and then set my static block in the router behind it OR would I set the dsl modem with my static IP block router address and then program the router with the static block of addresses.

I am worried about purchasing the wrong equipment for the job.

Does anyone know how it would work.

thanks in advance
Question by:dexterhome
    LVL 3

    Expert Comment

    With ISP do you use? comcast/verizon from my experience push your static IP by the modem's MAC Address or something like that (means no matter how I connected, laptop straight to the modem or a cheap router, I always get my static IP).

    Worst case scenario, something happened and I lost my static IP, a simple reset to the modem get it back.

    Most of the routers works on DHCP and gets the modem's connections with no configurations from the router side.
    LVL 5

    Author Comment

    I am on BT ADSL (uk)
    LVL 5

    Expert Comment

    The IP addresses are dependent on your ISP.  Dynamic IP's are usually the norm for ADSL but for an upgrade in price your ISP will provide static IP's and those IP's can be registered for a domain name for your mail server.  Has your mail server been registered for a MX record?  
    LVL 5

    Author Comment

    Everything is woprking correctly and has requird at the moment.
    The problem is that the BT router loses all settings under a minor flux in power or a blip in the adsl data or even just looking at it can send it funny.
    It has NO backup/restore feature which is a good idea for a business class router so must be manually reconfigured which is long winded and anoying.

    I simply wished to replace it with a netgear device but they are advising to use a modem and then router configuration which I have never used with a static block of addresses.

    I am unsure on how a modem + router (separate devices) is to be configured with a static ip block making sure that outbound traffic is sent from the static ip.
    LVL 5

    Accepted Solution

    I have performed a remote office setup with that configuration.

    The ADSL connects with PPPoE and rarely get a static IP usually a dynamic IP but it will be in static IP block range...either the 1st IP address or the last one.  

    Then your router will be configured with static IP block and then you will have setup One to One NAT to your servers, pc's on the inside.
    LVL 5

    Author Closing Comment

    Because the answer does not fit my configuration correctly.

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