ZyXEL Communications Prestige 662HW Series User Manual page 127

request for that packet and allowed in. Conversely, an incoming packet masquerading as a
response to a nonexistent outbound request can be blocked.
♦ The firewall uses session filtering, i.e., smart rules, that enhance the filtering process and
control the network session rather than control individual packets in a session.
♦
The firewall provides e-mail service to notify you of routine reports and when alerts occur.
When To Use The Firewall
♦ To prevent DoS attacks and prevent hackers cracking your network.
♦ A range of source and destination IP addresses as well as port numbers can be specified within
one firewall rule making the firewall a better choice when complex rules are required.
♦ To selectively block/allow inbound or outbound traffic between inside host/networks and
outside host/networks. Remember that filters can not distinguish traffic originating from an
inside host or an outside host by IP address.
♦
The firewall performs better than filtering if you need to check many rules.
♦
Use the firewall if you need routine e-mail reports about your system or need to be alerted
when attacks occur.
♦ The firewall can block specific URL traffic that might occur in the future. The URL can be
saved in an Access Control List (ACL) database.
Firewalls
Prestige 662HW Series User's Guide
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