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After configuration is done, click
Apply
to make the
configuration take effect.
3.3.7
Firewall Settings
A denial-of-service (DoS) attack is characterized by an explicit
attempt by attackers to prevent legitimate users from using
that service. Examples include the following
°
The attackers attempt to flood a network, thereby
preventing legitimate network traffic
°
The attackers attempt to disrupt connections between
two machines, thereby preventing access to a service
°
The attackers attempt to prevent a particular individual
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from accessing a service
°
The attackers attempt to disrupt service to a specific
system or person.
Port scan protection is designed to block attempts to discover
vulnerable ports or services that might be exploited in an
attack from the WAN.
Choose
ADVANCED
>
Firewall Settings
. The page shown in
the following figure appears.
Click
Apply
to save the settings.
3.3.8
DNS
Domain name system (DNS) is an Internet service that
translates domain names into IP addresses. Because domain
names are alphabetic, they are easier to remember. The
Internet, however, is actually based on IP addresses. Each
time you use a domain name, a DNS service must translate
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the name into the corresponding IP address. For example, the
domain name www.example.com might be translated to
198.105.232.4.
The DNS system is, in fact, its own network. If one DNS
server does not know how to translate a particular domain
name, it asks another one, and so on, until the correct IP
address is returned.
Choose
ADVANCED
>
DNS
. The page shown in the
folllowing figure appears.
DNS SERVER CONFIGURATION
If you are using the device as DHCP server on the LAN, or if
you are using DNS servers provided by your ISP, select
Obtain DNS server address automatically
.
If you have DNS IP addresses provided by your ISP, enter
these IP addresses in the preferred DNS server and the
alternate DNS server field.
Click
Apply
to save the settings.
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59
3.3.9
Dynamic DNS
The device supports dynamic domain name service (DDNS).
The dynamic DNS service allows a dynamic public IP address
to be associated with a static host name in any of the many
domains, and allows access to a specified host from various
locations on the Internet. Click a hyperlinked URL in the form
of hostname.dyndns.org and allow remote access to a host.
Many ISPs assign public IP addresses using DHCP, so
locating a specific host on the LAN using the standard DNS is
difficult. For example, if you are running a public web server
or VPN server on your LAN, DDNS ensures that the host can
be located from the Internet even the public IP address
changes. DDNS requires that an account be set up with one
of the supported DDNS service providers (DyndDNS.org or
dlinkddns.com).
Choose
ADVANCED
>
Dynamic DNS
. The page shown in
the following page appears.
Click
Add
to add dynamic DNS. The page shown in the
following figure appears.
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°
DDNS provider
: Select one of the DDNS service
provider from the down-list. Available service providers
include DynDns.org and dlinkddns.com.
°
Host Name
: Enter the host name that you registered with
your DDNS service provider.
°
Username
: Enter the user name for your DDNS account.
°
Password
: Enter the password for your DDNS account.
Click
Apply
to save the settings.
3.3.10
Network Tools
Choose
ADVANCED
>
Network Tools
. The page shown in
the following figure appears.
19216811.live