Routers Administrator's Handbook

Administrator’s Handbook
24
As a device on the Internet, a Motorola 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 applica-
tions:
By receiving a response to a scan from a port or series of ports (which is the expected behavior accord-
ing 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 Motorola 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.
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
Firewall Setting >> Off
Low/Medium*
High
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 Netopia server Enabled Disabled Disabled
80 http external Enabled Disabled Disabled
80 http Netopia 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