I have to network 5 PC's that have different operating systems these need to talk to a local server do dump data to a shared folder in a lab. That Server needs to talk to another one in the computer room to dump data to a shared folder. I need to limit the traffic so the servers only talk to each other and other people on the network can not see the 5 PC's. Note I can not use a domain structure to do this. Maybe creating a separate work group? I have a few labs like this with a local server and all of them need to dump data to the central server. I just need to limit each lab so the pc's can only talk to each other and not outside the lab.

Not sure what servers/workstations you have, but I would do this: Setup a workgroup on the lab-server, and join all 5 workstations to that workgroup. Create a user on the central servers domain - ie LabSvr. Create the shared folder on the central server and give the user LabSvr write access in both the sharing and security permissions. On the lab-server, map a drive to the shared folder on the central server using the domain\LabSvr account to gain access, and tell it to keep the mapping. You could also setup a 2nd domain on the lab-server, and have the workstations join that domain. Then setup the needed trust between the two servers. Again, I can't tell you how to do that, as I'm not sure what OS you have on the servers/workstations.

Thanks. The server is Windows 2008 so that should not be a issue. The one issue I have is once these are all set up they do not want to be able to see the individual lab computers on the network. I figure I can just turn off sharing on these units but not sure how to totally hide them on the network. I do have a DOS based pc and I was going to just write a batch file to copy the data to the label server.

You could always add an extra NIC in the lab-server. Then you could create a separate IP network for the workstations and the lab-server NIC connected to them, and connect the other NIC to the central network. Make sure IP Routing is NOT enabled on the Lab-Svr. (above IP addresses are only as an example)