Multiple Online Sessions?

I’m trying to build a party system for my game, which is being built for Steam. Essentially I want players to be able to party up together as early as the main menu.

I’m trying to do a system similar to Gears of War 3 (or judgement, or 4) - where players can group up in the menus then search for games as a group. Steam doesn’t have any kind of Online Party Interface - so all I can think of at the moment is to host a ‘party session’ that players can join. Not yet sure how I’ll be able to handle joining sessions that have too few slots reliably.

It gets more complex than that. I also need a ‘Lobby’ session, since the server creates a public or private ‘lobby’ as well as their party - then in the lobby they can set the match settings. From the lobby they then progress into the actual match. When returning to the lobby from the match, all players in the match stay in the lobby. When returning to the menu from the lobby, all party players stay with their original party leader. “Party Slaves” as I’m coining them, can only vote on options in the lobby and leave / join other parties.

So the main question is, before I start making headway on this - is it even possible for a listen server to not only host multiple sessions, but host sessions while also joining others etc? Somehow I need a way for all the players to stick together like this.

I am not sure about you original question but it seems like UE4 has a “Party Beacon” but I couldn’t find the documentation for it. Here is a forum thread about it Party Beacon? How does it work? o.O - C++ Gameplay Programming - Unreal Engine Forums