The DNS server has a host name, domain name of the email address, etc. in association with the IP address information.
Communication is impossible if the other party is described by host name, domain name, etc. when the computer or the printer performs IP communication.
Queries the DNS server for that information and gets the IP address of the other party. This process is called name resolution.
Therefore, the devices such as computers and printers can communicate using the IP address.
Name resolution is necessary for the printer to communicate using the email function or Internet connection function.
When you use those functions, make the DNS server settings.
When you assign the printer's IP address by using the DHCP function of the DHCP server or router, it is automatically set.
The proxy server is placed at the gateway between the network and the Internet, and it communicates to the computer, printer, and Internet (opposite server) on behalf of each of them. The opposite server communicates only to the proxy server. Therefore, printer information such as the IP address and port number cannot be read and increased security is expected.
When you connect to the Internet via a proxy server, configure the proxy server on the printer.