An information transmission method in a control convergence-based core network architecture, wherein a convergence control plane of the control convergence-based core network architecture includes a network element selector, NES, and a plurality of controllers, each of the controllers implementing functions of registration management, authentication management, mobility management and paging management, comprising: receiving, by the NES, a first message from an external network element, wherein the first message comprises identification information of user equipment, UE (S301); determining, by the NES based on the identification information of the UE, a first user group to which the UE belongs (S302); determining, by the NES, a first controller corresponding to the first user group based on a preset correspondence between a user group and a controller (S303); and sending, by the NES, the first message to the first controller (S304), characterized in that the method further comprises: receiving, by the NES, a fourth message, wherein the fourth message comprises an identifier of a third controller and a user group list migrated from the first controller to the third controller (S802); and adding, by the NES in the preset correspondence between a user group and a controller, the user group list migrated to the third controller to a correspondence to the third controller in the preset correspondence, and deleting the user group list migrated to the third controller from a correspondence to the first controller (S803) in the preset correspondence. receiving, by the NES, a first message from an external network element, wherein the first message comprises identification information of user equipment, UE (S301); determining, by the NES based on the identification information of the UE, a first user group to which the UE belongs (S302); determining, by the NES, a first controller corresponding to the first user group based on a preset correspondence between a user group and a controller (S303); and sending, by the NES, the first message to the first controller (S304), characterized in that the method further comprises: receiving, by the NES, a fourth message, wherein the fourth message comprises an identifier of a third controller and a user group list migrated from the first controller to the third controller (S802); and adding, by the NES in the preset correspondence between a user group and a controller, the user group list migrated to the third controller to a correspondence to the third controller in the preset correspondence, and deleting the user group list migrated to the third controller from a correspondence to the first controller (S803) in the preset correspondence. receiving, by the NES, a fourth message, wherein the fourth message comprises an identifier of a third controller and a user group list migrated from the first controller to the third controller (S802); and adding, by the NES in the preset correspondence between a user group and a controller, the user group list migrated to the third controller to a correspondence to the third controller in the preset correspondence, and deleting the user group list migrated to the third controller from a correspondence to the first controller (S803) in the preset correspondence. <EOS>