It's a bit clunky but if you create an access control group and give it custom permissions then set like this:
It appears (and you will need to check all your use cases) that this stops a user getting into the space.
Caveat - not tested if this 'wins' when the user has a discrete override.
Edit: a discrete override wins over the the group 'no access' - so it is not foolproof.
Hi John, thanks by your advice. But it does not work.
I may relate wrongly my need.
I need to provide permissions for specific group only just over a created space. I mean the people defined into the group only should have access in the desired space.
I tried to follow your suggestion over default space permissions to limit the group access but it does not work.
Could you suggest a new approach to solve my problem?
Oh OK I thought you wanted to stop users in a permission group from having access to a particular space.
To limit users in a permission group to a single space or group, and to stop them from getting into other 'public' areas, sometimes called 'walled gardens', and to stop them seeing people in the people directory who do not have access to that space or group, and vice versa, is currently being worked on by Jive.
I don't know how your instance is currently set up but the only way of protecting the content for now would be to not have any public areas, or at least to only have content in any public areas that your group of users could see.
You are in good company as there are a number of customers talking in Engage Partners who have this requirement. There is also the issue of authentication, does your specific group have accounts on your instance (perhaps in your LDAP) or are they external users.