All networking solutions would require you to have some kind of a meeting hub where players can meet one another, whether it's Photon, TNet or uLink. If they are on the same LAN, this limitation can be avoided as it's possible to broadcast messages over LAN. You can't broadcast messages over the internet, however -- which is why you have to have a meeting place (lobby server). A dedicated server to host it is a must in this case.
Photon is the same -- but if you use Photon Cloud then you will have dedicated servers available for you to use already, which is convenient (but of course you share them with everyone else).
You could make a hybrid system where you use the photon cloud to meet people, then TNet for actual hosted games / multiplayer, but I would generally just recommend creating an Amazon EC2 instance to put your lobby server on. It's inexpensive (free for an entire year actually -- great for development), and will give you an idea of what you need.