Canon LBP7780CX User Manual page 447

When [Off] is selected using [Select Protocol], set the following items.
[IP Address]
[Subnet Mask]
[Gateway Address]
(3) Set DNS.
[Primary DNS
Server Address]
[Secondary DNS
Server Address]
[Host Name]
[Domain Name]
[DNS Dynamic
Update]
(4) Set DHCP option settings.
Enter the printer's IP address.
Enter the subnet mask used by the TCP/IP network.
Enter the gateway address used by the TCP/IP network.
Enter the IP address of the primary DNS server.
Enter the IP address of the secondary DNS server.
Enter the host name to be added to the DNS server. Up to 47 characters can be
entered.
Enter the name of the domain to which the printer belongs. Up to 47 characters can
be entered.
Entry example: "example.com"
Select the check box when using the DNS Dynamic Update function. When you are
not using the DNS Dynamic Update Function, clear the check box.
Using the DNS Dynamic Update function, by registering the [Host Name] and
[Domain Name] to the DNS server, the printer's IP address can be used
without being fixed.