Billion Electric Company 5100S User Manual

 

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passed to the client machines along with the assigned IP address and subnet mask. 

There are two ways that an ISP disseminates the DNS server addresses. The first is for an ISP 

to tell a customer the DNS server addresses, usually in the form of an information sheet, when 

s/he signs up. If your ISP gives you the DNS server addresses, enter them in the DNS Server 

fields in DHCP Setup, otherwise, leave them blank. 

Some ISP’s choose to pass the DNS servers using the DNS server extensions of PPP IPCP 

(IP Control Protocol) after the connection is up. If your ISP did not give you explicit DNS 

servers, chances are the DNS servers are conveyed through IPCP negotiation. The BIPAC 

5100S supports the IPCP DNS server extensions through the DNS proxy feature. 

If the Primary and Secondary DNS Server fields in DHCP Setup are not specified, for instance, 

left as 0.0.0.0, the BIPAC 5100S tells the DHCP clients that it itself is the DNS server. When a 

computer sends a DNS query to the BIPAC 5100S, the BIPAC 5100S forwards the query to the 

real DNS server learned through IPCP and relays the response back to the computer. 

Please note that DNS proxy works only when the ISP uses the IPCP DNS server extensions. It 

does not mean you can leave the DNS servers out of the DHCP setup under all circumstances. 

If your ISP gives you explicit DNS servers, make sure that you enter their IP addresses in the 

DHCP Setup menu. This way, the BIPAC 5100S can pass the DNS servers to the computers 

and the computers can query the DNS server directly without the BIPAC 5100S’s intervention. 

Use DNS (Domain Name System) to map a domain name to its corresponding IP address and 

vice versa. The DNS server is extremely important because without it, you must know the IP 

address of a computer before you can access it. 

There are two ways that an ISP disseminates the DNS server addresses. 

1. The ISP tells you the DNS server addresses, usually in the form of an information sheet, 

when you sign up. If your ISP gives you DNS server addresses, enter them in the DNS Server 

fields in DHCP Setup. 

2. Leave the DNS Server fields in DHCP Setup blank (for example 0.0.0.0). The BIPAC 5100S 

acts as a DNS proxy when this field is blank. 

The BIPAC 5100S has built-in DHCP server capability that assigns IP addresses and DNS 

servers to systems that support DHCP client capability. 

The LAN parameters of the BIPAC 5100S are preset in the factory with the following values: 

 

IP address of 192.168.1.254 with subnet mask of 255.255.255.0 (24 bits)