A method includes: receiving, by a first session management function network element, first identification information from an access and mobility management function network element; obtaining information about a plurality of anchor user plane function network elements of a first session based on the first identification information; and sending, by the first session management function network element, the information about the plurality of anchor user plane function network elements to a branching point, where the branching point is a user plane function network element that is managed by the first session management function network element and that has a function of diverting traffic.