Netopia 6.3 - Manual (Page 71)

71
Section 4 Configure
Basic Firewall Background
As a device on the Internet, a Cayman 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-con-
nected device.
To protect LAN users and their network from these types of attacks, Break-
Water offers three levels of increasing protection.
The following tables indicate the state of ports associated with ses-
sion types, both on the WAN side and the LAN side of the Gateway.
This table shows how inbound traffic is treated. Inbound means the traffic is
coming from the WAN into the WAN side of the Gateway.
• ICMP • HTTP • FTP
• SNMP • telnet • DHCP
Gateway: WAN Side
BreakWater Setting >> ClearSailing SilentRunning LANdLocked
Port Session Type --------------Port State-----------------------
20 ftp data Enabled Disabled Disabled
21 ftp control Enabled Disabled Disabled
23 telnet external Enabled Disabled Disabled
23 telnet Cayman server Enabled Disabled Disabled
80 http external Enabled Disabled Disabled
80 http Cayman server Enabled Disabled Disabled
67 DHCP client Enabled Enabled Disabled
68 DHCP server Not Applicable Not Applicable Not Applicable
161 snmp Enabled Disabled Disabled
ping (ICMP) Enabled Disabled Disabled