Yes your institution automatically logs you out every 15 minutes after inactivity. This is a feature of the Bluesocket network and there is nothing anyone can do about it. BlueSocket Authenticator just makes it easier for your to log in with 1 click rather than having to enter your credentials in Safari every time.
So every time you are on your institutions network you should click the Bluesocket Icon to log you in and then you are good. You can also change the Setting to automatically close BA after authentication so it doesn't even show you the "Authenticated Successfully" screen it just flashes and saves you 1 more click.