Public computer control

[antonio.montagnani at alice.it]

We are installing linux on public library network

I have two easy questions:


1) how can I control time of a session, i.e. to have logout automatically after 
a certain time from login?? 
2) how can I make all personal data flushed at 
logout??

Any applications available?? 

Any experience in library installation 
of Fedora???

Tnx

Antonio