User manual

106
7.1.4. Session Limit
To prevent ill-behaved clients or malicious software from using up the system’s connection resources, the
administrator can restrict the number of concurrent sessions that a user can establish.
The maximum number of concurrent sessions (TCP and UDP) for each user can be specified in the Global
policy, which applies to authenticated users, users on a non-authenticated port, privileged users, and
clients in DMZ zones. Also this can be specified in the other policies to apply to the authenticated users.
When the number of a user’s sessions reaches the session limit, the user will be implicitly suspended upon
receipt of any new connection request. In this case, a record will be logged to a Syslog server.
Since this basic protection mechanism may not be able to protect the system from all malicious DoS
attacks, it is strongly recommended to build some immune capabilities (such as IDS or IPS solutions) in
network deployment to maintain network operation.