Online server, non-dedicated, Mod question

[UnknownFox]

So, maybe obvious but in my google searches I wasn't really getting any answer. If I am running a server for me and a few people by just hosting a single player server and turning it online (Open to Lan > Open to Online) do all people connecting need the same mods? I assume yes, but I wanted to confirm before I go downloading a bunch and sending out the list to them.

[Whiteindia]

I believe they all have to have the same server side mods, but the server generally will download them for them when they try to join.