User manual

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6.3.5 Session Limit
To prevent ill-behaved clients or malicious software from taking 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 including 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 (a choice of Unlimited, 10, 25,
50, 100, 200, 350 and 500), 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.