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4. You may add more firewall rules
for specific security purposes.
Click on the Add radio button at
the screen shown above,
followed by the Edit button and
the screen on the left will
appear.
Rule Name : Enter a unique name to identify this firewall rule.
Disposition
Policy : This parameter determines whether the packets obeying
the rule should be accepted or denied by the firewall.
Choose between Accept and Deny.
Protocols : Users are allowed to select the type of data packet
from: TCP, UDP, ICMP, IGMP or ALL.
Note: If users select either ICMP or IGMP, they are
required to make further selection in the ICMP Types or
IGMP Types respectively.
ICMP Types
: This IP protocol is used to report errors in IP packet
routing. ICMP serves as a form of flow control, although
ICMP messages are neither guaranteed to be received
or transmitted.
ICMP
Packet Type Description
Echo
request Determines whether an IP
node (a host or a router) is
available on the network.
Echo reply Replies to an ICMP echo
request.
Destination
unreachabl
e
Informs the host that a
datagram cannot be
delivered.
Source
quench Informs the host to lower the
rate at which it sends