I am looking for a discussion forum web application with these features:
- People can register themselves and maintain a very simple profile
- The webapp basically consists of a set of discussion channels
- Each channel can be open to anyone registered or open (readable and writable) only for a certain selected users
- Discussion channel allows anyone with access to write comments and replies to comments (i.e. classical nested view of discussion like we know it from any discussion forum). I.e. a channel is simply a typical discussion forum where one can comment and reply, no special features needed.
- Moderation features welcome but not necessary, e.g. the possibility of a moderator to remove certain comments or all comments of a user or ban user from a channel.
- At least one admin can administer registered users. He can see who is registered. He can deactivate account of any user (the user will no more be able to log in).
- At least one admin can easily create new channels and assign and remove users from/to these channels.
- The channels are not visible to everyone, only to those people who have access to them.
- The privacy of the channels and access control to them is an essential MUST HAVE feature
- Allows for some sort of e-mail notifications about new comments for users of a channel
- People have some page where they can see their channels and how many new messages they have in their channels e.g. since their last visit or yet unread.
- Good if channels could have some sort of description that could be easily changed by the admin or moderator
- The web app should preferably be on premise so that I can install it on my own server. It could also be cloud-based in case there is a reasonable guarantee that nobody will see any data in the channels, only those permitted ones.
- It does not have to be a fully professional and perfect solution corporate-world-ready. No super design necessary. More like a simple tool but without bugs, enough tested and used, with some support from a community or company
- Installing and administering the tool is not very complex and does not require some specific experience or knowledge besides standard administration skills of someone who can run a PHP/Mysql/Wordpress site of a small scale
- Cheap price, let's say lower hundreds of dollars per year per 1000 users and 1000 channels (really just approx numbers). Can also be open source or free or anything if quality good enough (without bugs).
I bet there are really many community products and collaboration tools of this sort. I need a recommendation from someone who has experience with the tool and can decribe how much the tool fits into my requested features. Thanks in advance for your time helping me.