Information obtaining method and apparatus, and system

A communication system, wherein the communication system comprises:

• a first policy control network element and a binding support function network element,
• wherein the first policy control network element includes first one or more processors and a first memory,
• wherein the binding support function network element includes second one or more processors and a second memory,
• wherein the first policy control network element is configured to:
• receive first information of a user equipment from an application function network element, wherein the first information comprises session information of the user equipment, and the first policy control network element decides a mobility management policy based on the first information;
• and
• send, to the binding support function network element, a message for obtaining information about a second policy control network element, wherein the second policy control network element serves a session corresponding to the session information,
• wherein the message for obtaining the information about the second policy control network element comprises the session information and first indication information, and the first indication information indicates a condition for sending the information about the second policy control network element;
• and
• wherein the binding support function network element is configured to:
• receive, from the first policy control network element, the message for obtaining the information about the second policy control network element.

An apparatus, comprising:

• one or more processors and a memory, wherein the memory is configured to store a computer program, and the one or more processors are configured to invoke and run the computer program stored in the memory, to cause the apparatus to perform operations including:
• receiving first information of user equipment from an application function network element, wherein the first information comprises session information of the user equipment, and the apparatus decides a mobility management policy based on the first information;
• and
• sending to a binding support function network element, a message for obtaining information about a second policy control network element, wherein the second policy control network element serves a session corresponding to the session information, and
• wherein the message for obtaining the information about the second policy control network element comprises the session information and first indication information, and the first indication information indicates a condition for sending the information about the second policy control network element.