ZyXEL Communications LTE5121, Руководство пользователя

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Chapter 12 Firewall
LTE-5121 User’s Guide
131
12.5 The DoS Screen
Click Security > Firewall > DoS to display the following screen. Use this screen to enable or
disable Denial of Service (DoS) protection.
Figure 90
Security > Firewall > DoS
Each field is described in the following table.
Protocol This field is available when you select Select Service in Select Protocol.
Choose the protocol type (TCP, UDP, ICMP or Others) of the service.
Protocol Number This field is available when you select Others in Protocol.
Enter the protocol number of the service type to which this ACL rule applies.
Source Port This field is displayed only when you select Select Service in Select Protocol and TCP
or UDP in Protocol.
Select Single or Range and then enter a single port number or the range of port
numbers of the source. Select Any to indicate any source port.
Destination Port This field is displayed only when you select Select Service in Select Protocol and TCP
or UDP in Protocol.
Select Single or Range and then enter a single port number or the range of port
numbers of the destination. Select Any to indicate any destination port.
Policy Use the drop-down list box to select whether to silently discard (DROP), deny and send
an ICMP destination-unreachable message to the sender of (REJECT) or allow the
passage of (PERMIT) packets that match this rule.
Direction Use the drop-down list box to select the direction of traffic to which this rule applies. The
possible options are LAN to DEVICE, LAN to WAN, WAN to LAN, and WAN to
DEVICE.
Apply Click Apply to save your changes.
Back Click Back to exit this screen without saving your changes.
Table 50
Security > Firewall > Access Control > Add New ACL Rule/Edit (continued)
LABEL DESCRIPTION
Table 51
Security > Firewall > DoS
LABEL DESCRIPTION
DoS Protection
Blocking DoS (Denial of Service) attacks can flood your Internet connection with invalid packets
and connection requests, using so much bandwidth and so many resources that Internet
access becomes unavailable.
Select Enable to enable protection against DoS attacks or Disable to disable it.
Apply Click Apply to save the DoS Protection settings.
Cancel Click Cancel to restore your previously saved settings.