Thanks, all, I don't think a switch is exactly what I need. The setup will be 3 or 4 computers that run cameras and talk with another that provides the GUI for the operator. They will all run LINUX, Ubuntu at the moment, and it appears that IPv6 is supported. The Network Time Server is probably not and it's not clear if it is upgradeable.
Either the computer that suports the GUI or the operators notebook will make connections out via the satellite to upload data to our ground station (ISP). I expect to use some other notebooks for trouble shooting and maintenance and want DHCP for them.
I've just finished writing and testing my networking module (using IPv4 of course) and I wrote it so the only IP addresses that must be static are the master computer with the GUI and the NTS.
I don't want any communications coming into the aircraft from the ground on this system so thought that everything could "hide" behind the router. The SATCOM can be ordered with a very expensive router that provides only 6 ports. We don't have the well over $1,000 for the builtin and can't turn it on in the hanger for system maintenance in any case.
I should be speaking to the head of telecommunications for USDA to find out which of their rules apply to this project. But, at least I can say that it will have an IPv6 router!