As an Administrator I would like to be able to disable public access to JIRA, so the users will have to login before they can browse projects, search issues or navigate to system dashboard.

Workaround:
In JIRA 7.2.10 the possibility to disable public access for anonymous users was added, however it is still in labs state.

In order to disable public access for anonymous users, administrator needs to add a darkfeature public.access.disabled.
Here are the steps required for adding a dark feature in Jira:

• Login as an administrator and go to: [BASE-URL]/secure/SiteDarkFeatures!default.jspa
• In the Enable Dark Feature text field add public.access.disabled