Teletronics EZStation5 - Manual (Page 153)

Page 153
You may add more firewall rules for specific security purposes. Click on the A A d d d d
radio button at the screen shown above, followed by the E E d d i i t t button.
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
unreachable Informs the host that a datagram
cannot be delivered.
Source quench Informs the host to lower the rate at