1 Computer shared on 2 separate networks

[fetster]

I have a laptop that is connected to a restaurant till system back of house PC which mirrors the till system software (Stock control & reports etc).

The Back Of House PC and laptop are on their own network and have their own ADSL internet connection.

We are looking to connect the restaurant to our own LAN with a fibre cable so the managers can join our network rather the ADSL connection in the restaurant and share our resources.

At the moment we log in remotely to the laptop with Logmein / Net Support Software through the ADSL connection.

Could I join our network to the network their so the laptop can be accessed locally rather than through internet connection? I still want the till system etc to use the ADSL connection there.

I'm not sure if this question is making sense - I effectively want a computer to be a member of network A & B but none of the other devices on Network A to talk to Network B Devices and Vice versa.

Can this be done, if so what do I need to look up?

Thanks

 

[fetster]

Both networks A and B have their own Internet connections.

I want all of the computers on network A to be able to connect to the laptop on network B but nothing else on network B. The laptop on Network B connects to the till computer on network B. Other than the laptop on network B I don't want anything else on network B communicating with network A. Both networks A and B have their own ADSL connections using different draytek routers.

Regards

Fetster

 

[fetster]

Just a follow on Query ....
I am installing Netgear GS724 managed switches on the network. Would setting up a few VLANs do the trick?

I am completely new to VLANs and apologise if the question sounds as daft as some of the replies above.

If I was to set up the Back of house computer and restaurant router and tills etc on VLAN 1.
Set up the same back of house computer and the laptop on VLAN 2.
Set up the laptop and fibre connection (and other devices on office network) on VLAN 3.

Would this allow:
Back of house PC to access its own ADSL connection.
Laptop to access back of house PC.
Office network to access the laptop.
No other PCs to cross access back of house PC and vice versa.

Would this work?