User guide

36
Firewall Background
The following table gives some tips for Firewall settings:
As a device on the Internet, a Netopia Gateway requires an IP address in order to send or
receive traffic.
The IP traffic sent or received have an associated application port which is dependent on
the nature of the connection request. In the IP protocol standard the following session
types are common applications:
By receiving a response to a scan from a port or series of ports (which is the expected
behavior according to the IP standard), hackers can identify an existing device and gain a
potential opening for access to an internet-connected device.
To protect LAN users and their network from these types of attacks, the Netopia Firewall
offers three levels of increasing protection.
The following tables indicate the state of ports associated with session types, both on the
WAN side and the LAN side of the Gateway.
Application
Select this
Level
Other Considerations
Typical Internet usage
(browsing, e-mail)
Medium
Multi-player online
gaming
Low Set up “Gaming” on page 51; once defined,
services will be active whenever Off is set.
Restore Medium when finished.
Going on vacation High Protects your connection while you’re away.
Finished online use for the
day
High This protects you instead of disconnecting
your Gateway connection.
Chatting online or using
instant messaging
Off Set up “Gaming” on page 51; once defined,
services will be active whenever Off is set.
Restore Medium when finished.
• ICMP • HTTP • FTP
• SNMP • telnet • DHCP