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SECURITY BASICS
Control the traffic
A firewall blocks uninvited Internet traffic that might cause damage to the computers in your net-
work. Before traffic is allowed in or out of your network, it has to pass through the firewall. Incoming
traffic is examined to see whether it meets the conditions of incoming rules. If the conditions are
met, the traffic is allowed in. Outgoing traffic is also examined and compared to outgoing rules
before it is allowed out. Rules are based on Internet services, such as FTP, Telnet and NetMeeting.
Is it necessary to change the default firewall rules or add new rules?
For private use, you should not have to add new rules or change the default rules.
By default, all incoming traffic is blocked and all outgoing traffic is allowed. If you set up a
virtual server, an additional incoming rule is automatically added to enable access to the server
from the Internet.
An example of an attack that your GlobeSurfer®II will automatically block is a Denial of Service (DoS)
attack. This is an attack where a hacker chooses to flood your network with more requests than it
can handle. While this type of attack would not harm computers in the network, it could slow or
even stop network operations. You do not need to set up a firewall rule for this.
More information about the firewall and applying corporate grade security is provided in the
‘Reference Manual’.`
IP- Hostname (url) Filtering
You may configure GlobeSurfer®II to block specific Internet sites so that they cannot be accessed
from computers in the local network. Moreover, restrictions can be applied to a comprehensive, auto-
matically updated, table of sites to which access is not recommended.
To view the table of Web sites currently being blocked:
•
Click the ‘IP/Hostname Filtering’ tab located under Security.
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