Multiple DNS addresses are useful to provide alternatives when one of the servers is down or is encountering heavy traffic. ISPs typically provide primary and secondary DNS addresses, and may provide additional addresses. Your LAN PCs learn these DNS addresses in one of the following ways:
zStatically: If your ISP provides you with their DNS server addresses, you can assign the addresses to each PC by modifying the PCs' IP properties.
zDynamically from a DHCP pool: You can configure the DHCP Server feature on the ADSL/Ethernet router and create an address pool that specify the DNS addresses to be distributed to the PCs.
5.7.7Blocked Protocols
The ADSL/Ethernet router is capable of sending and receiving information in a variety of protocol formats. The Blocked Protocols feature enables you to prevent the ADSL/Ethernet router from passing any data that uses a particular protocol. Unlike the IP Filter feature, you cannot specify additional criteria for blocked protocols, such as particular users or destinations. However, when you are certain that a particular protocol is not needed or wanted on your network, this feature provides a convenient way to discard such data before it is passed.
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