#8 FIFO with priority policy
FIFO with priority would be the policy running now in the observatory. In the future we would test other policies.
At this moment we have 3 roles, admin, advanced and basic.
Since advanced users need to make tests every single day, they will have priority. Therefore, the basic users will be throw out automatically when some "advanced" user log in and after a confirmation. The system will inform about this fact to rest of the users.
What to do in case several users of the same level (Karma??) log in the system? This concurrency problem would be solve by this way; the observatory will belong to the first who logged in. The second user of the same level will be able to see who has the control, what he/she is doing, and he/she be able to ask for the control via the chat. Therefore any user who has the control of the observatory would be able to free the observatory either by logging off the system or by pressing a buttom.
There will be a queue of people waiting for the observatory, therefore the observatory would be for the first user in the queue. In the future we could also order this queue by karma.