Members Only Section?

Hi there,

I tried searching a few places, but I get a lot of options, and I’m just trying to figure out the best one. Does anybody have experience with this?

I need to have a “Group Members Only” section, where:

• There’s a form to fill out your username/password on the login page (www.domain.com/login)
• The links inside there, are members only, too (www.domain.com/login/apage/)
• Each member can “register” and create their own username and password

How would I go about doing this? Preferably free ??