Hi Vivien,
--> authenticate user without the use of SSL
you cannot use Shield in that version without SSL. Here's another post on it;
In the 5.0 stack SSL is not required.
--> allow or not to use the discover part of kibana
There is not any supported way to disable Discover. I think some people have put a proxy in front of Kibana to block requests to /discover, but I don't know any details on that approach.
--> allow or not to use the view of some visualization
I think you could use document level security to create a role which does not have access to some visualizations. I'll try to do this and update with the results.
--> Use the plugin shield for kibana (actually i can't when i launch kibana an error occur on the existence of ssl option)
Yes, you must use SSL with the Kibana Shield plugin in Kibana 4.x.
Regards,
Lee