How to use 1 DSL modem to serve 2 networks

[jferrante]

Goal is to have 2 separate networks share 1 DSL modem connection.

I'm not even sure if this is the appropriate forum.

I have read somewhere on Tek-tips, directions to do this using 3 routers (I can’t find it), but can I do it with 2? Here’s my setup:

Network 1. Peer network for workbench use here. I only need internet access when I set up a new or refurbish a customer computer and don’t want to bother with server logons, etc.

Network 2. SBS2003. Server has 2 network cards. One for internal network, one for the router connection. This will be my office network.

Currently using a Linksys BEFSR41 router which is connected to my DSL modem and is set to it's default IP of 192.168.1.1. It is serving as a DHCP server to my peer network with it’s default scope of 192.168.1.100 etc

What I’m thinking is, add a second SR41, let it get it’s IP from the first router — either static or by DHCP. Plug the SBS 2003 second network card in to it. Use a scope of 10.0.0.x or something on the second Linksys.

I’m having trouble thinking this through with various subnets, etc. Any help would be appreciated.

Thanks in advance,

Jeff

 

[bcastner]

Why have two network segments at all?

The fact that you have a Domain network on the same subnet does not mean that you have to authenticate to it.

 

[jferrante]

Could you explain just a little more?

 

[bcastner]

Since your existing router is supplying DHCP IPs, just plug a bench workstation into the device. If you need more ports, use a switch connected between the cross-over port on your existing router and a normal LAN port on the switch.

Unless you make the effort to create a machine account and a user account, and specify in System Properties a Domain setting, the machine will simply pull an IP from the router - including the router as the Gateway address, and be able to work as a stand-alone workstation and have internet access. It will never know the SBS Domain is on the same subnet.

Any security concerns should be dealt with by enabling a firewall. By default or by user configuration you can tell it to ignore any communications from and to a range of IP addresses on the subnet.

 

[jferrante]

Thanks. I'm a little brain dead today.

 

[MJewell]

However if you wanted to make a clean network for bringing up new machines that are not patched yet. I would take the extra router and plug it in to the same lan segment as the SBS and the DSL line. Then if a virus were running around in your SBS network, it would not affect the new machine untill you phisically moved it to the SBS network. Although you need to make sure you give it a different subnet...

DSL
|
Router---SBS
|
Router---Clean Network

-Mike