Domain name system server determining method, and request processing method, apparatus, and system

A communication method, comprising:

• determining, by a session management function network element and based on a first location of user equipment, a data network access identifier (DNAI) indicating a deployment location of a first application;
• determining, by the session management function network element and based on the DNAI, a first local domain name system server's address that corresponds to the DNAI, wherein the first local domain name system server is a local domain name system server that resolves the domain name of the first application into a corresponding first Internet protocol address, and the first Internet protocol address is associated with the first location;
• sending, by the session management function network element, the first local domain name system server's address to a first device;
• and
• receiving, by the first device, the first local domain name system server's address.