It's better if the hub and the Telo are each plugged into the router. If there aren't enough ports available on the router, inexpensive switches are available to expand the number of ports on your router.
Telo with 2 Handsets, a Linx, and a Safety Phone
Telo2 with 2 Handsets and a Linx
A Telo can plug into your network the same way a pc can. The Telo is a router in itself and you can plug pc's into it via the HOME/NETWORK port.
If you connect just a modem, the Telo should connected fine. Connect any pc's to the HOME/NETWORK port of the Telo using the hub.
So it would look like this:
modem-->Telo-->hub (or pc)
modem-->router-->Telo (if you are using a router)
When adding or changing your network setup make sure to power cycle everything to refresh the changes.
Tell us more about your setup and what the Telo is doing/notdoing.