Netopia 6.3 manual Local Area Network, DNS Proxy

Section 3 General

Local Area Network

DHCP (Dynamic Host Configuration Protocol) Server

DHCP Server functionality enables the Gateway to assign your LAN com- puter(s) a “private” IP address and other parameters that allow network communication. The default DHCP Server configuration of the Gateway supports up to 253 LAN IP addresses.

This feature simplifies network administration because the Gateway main- tains a list of IP address assignments. Additional computers can be added to your LAN without the hassle of configuring an IP address.

DHCP (Dynamic Host Configuration Protocol) Relay Agent

DHCP Relay functionality enables the Gateway to forward a DHCP client request to a specified DHCP Server. This assigned DHCP Server will reply to the request with an IP address and other network parameters.

DNS Proxy

Domain Name System (DNS) provides end users with the ability to look for devices or web sites through the use of names, rather than IP addresses. For websurfers, this technology allows a user to enter the URL (Universal Resource Locator) text string to access a desired website. Each text string identifier has an associated IP address, a series of numbers in the format of xxx.xxx.xxx.xxx (e.g. 147.240.101.006). It is DNS servers that are respon- sible for this text-to-IP Address translation. DNS Servers, in most cases, are located at Internet Service Provider facilities. They translate domain names into the desired IP address for locating an Internet website by answering DNS requests.

The Cayman DNS Proxy feature allows the LAN-side IP address of the Gate- way to be used for proxying DNS requests from hosts on the LAN to the DNS Servers configured in the gateway. This is accomplished by having the Gateway's LAN address handed out as the “DNS Server” to the DHCP cli- ents on the LAN.

The Cayman DNS Proxy only proxies UDP DNS queries, not TCP DNS queries.

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