In Tony Hawk's Pro Skater 4, a broadband online room could host up to eight people.
The game offered online multiplayer through its PlayStation 2 and PC versions, using an Internet connection and the relevant network hardware or service. The broadband limit was eight hosted players, allowing larger sessions than the game's dial-up option.
Connection type mattered: dial-up hosting was limited to three people, while players using either connection could join an existing room. This distinction is why references to the game's online capacity sometimes appear to give different numbers. The question asks specifically about a broadband-hosted room, making eight the precise answer.
Online modes included Trick Attack, Graffiti, Combo Mambo, King of the Hill, Slap and Free Skate. Pro Skater 4 was released in 2002, when broadband multiplayer was still a notable feature rather than a standard expectation. Its online support helped extend the series' trick-scoring competition beyond local multiplayer.