I think you’re right Ben. And this makes it strange: to get inconsistent behaviour depending on the network!

I have a router that I know was causing some problems with uRADMonitor units. I’ll need to find it and run some tests before I can report back.

The DHCP code was mainly written by me, and in the last revision I added the hostname option (in the form uRADMonitor-). Previously you would only see the MAC, the allocated IP and no hostname. I might have done something wrong so hopefully things will clarify.

Another option is checking it against the Arduino implementation, but I find that complicated with all the Arduino libs and custom I/O code.