Wired LAN, wireless Internet, same PC? How?

[lindochico]

Hello guys,

The company I work for is planning on setting up a LAN in order to share resources from a file server (Dell Poweredge 2600). Currently, we have about 15 computers (Win XP Home) connected to a wired hub (3Com OfficeConnect 16) which is in turn connected to a DSL router (Cisco 857) for internet connection.

The plan is to install wireless network cards (probably from D-Link) on some of our computers and use a wireless hub (D-Link DI-624) to connect it to the DSL router, and then use the wired hub to make another separate network to connect some other computers to the server. The thing is that we want some of these computers to be connected to the server and to the internet at the same time without exposing our internal LAN to the internet.

What would be the right configuration in order to achieve this, so that Internet Explorer knows which connection to use to access the internet and still have access to the server through the other programs and systems? Do we need more special hardware or is it just enough to play with the IP addresses? What would be the right procedure for this?

If you need any more info, please let me know.

Thank you for your help.

[ErikD]

Pretty simple. Setup the wired network to be some IP range, say 192.168.0.x, and the wired to be another, say 10.0.0.x. Then give the wired connections an IP address in the wired range, subnet mask, and DNS server, but NO default gateway. Give wireless IP, subnet, default gateway, DNS.

Now when the computer looks to send something to an unknown address its only choice is the connection with a default gateay. So all internet traffic is by definition off of your network (unknown) and is forced through wireless.

[YeOldeStonecat]

What EricD stated above is probably the easiest method to do what you ask...but IMO it doesn't minimize risk. If a computer is connected to the internet, it can bring in problems. If it's connected to a LAN, it can spread those problems. Even though you're hitting the internet through LAN A, and not through LAN B, the fact that an internet able PC is connected to LAN B still allows it to be an avenue for problems to hit LAN B. To simplify it...bad guys can come IN through the wireless NIC and OUT through the wired NIC.

The plan is to install wireless network cards (probably from D-Link) on some of our computers and use a wireless hub (D-Link DI-624) to connect it to the DSL router, and then use the wired hub to make another separate network to connect some other computers to the server. The thing is that we want some of these computers to be connected to the server and to the internet at the same time without exposing our internal LAN to the internet.

[lindochico]

Finally! Connection works like a charm!

Now, on the security issue: every PC has a firewall installed and also our Cisco router comes with a firewall integrated. Isn't this secure enough or should I implement anything else?

I have configured WEP encryption and MAC address access on the wireless AP too.