A method, wherein, when at least two sessions exist between a user equipment, UE, and a data network via an Access Network, AN, apparatus and a User Plane, UP, of a core network, the method comprises the following steps performed by the AN apparatus: receiving session attributes of the UE from a control plane, CP, network element of the core network, the session attributes comprising a bandwidth constraint condition corresponding to each of the at least two sessions; and controlling the UE based on the session attributes by: calculating, based on the bandwidth constraint condition corresponding to each of the at least two sessions, a sum of bandwidth constraint conditions corresponding to the at least two sessions; obtaining, from the CP network element, a subscribed bandwidth constraint condition of a user packet; and when the sum of bandwidth constraint conditions is greater than the subscribed bandwidth constraint condition of the user packet, performing, based on the subscribed bandwidth constraint condition of the user packet, bandwidth constraint on a downlink user packet received by the AN apparatus from the UP and forwarded by the AN apparatus to the UE; or when the sum of bandwidth constraint conditions is less than or equal to the subscribed bandwidth constraint condition of the user packet, performing, based on the sum of bandwidth constraint conditions, bandwidth constraint on a downlink user packet received by the AN apparatus from the UP and forwarded by the AN apparatus to the UE receiving session attributes of the UE from a control plane, CP, network element of the core network, the session attributes comprising a bandwidth constraint condition corresponding to each of the at least two sessions; and controlling the UE based on the session attributes by: calculating, based on the bandwidth constraint condition corresponding to each of the at least two sessions, a sum of bandwidth constraint conditions corresponding to the at least two sessions; obtaining, from the CP network element, a subscribed bandwidth constraint condition of a user packet; and when the sum of bandwidth constraint conditions is greater than the subscribed bandwidth constraint condition of the user packet, performing, based on the subscribed bandwidth constraint condition of the user packet, bandwidth constraint on a downlink user packet received by the AN apparatus from the UP and forwarded by the AN apparatus to the UE; or calculating, based on the bandwidth constraint condition corresponding to each of the at least two sessions, a sum of bandwidth constraint conditions corresponding to the at least two sessions; obtaining, from the CP network element, a subscribed bandwidth constraint condition of a user packet; and when the sum of bandwidth constraint conditions is greater than the subscribed bandwidth constraint condition of the user packet, performing, based on the subscribed bandwidth constraint condition of the user packet, bandwidth constraint on a downlink user packet received by the AN apparatus from the UP and forwarded by the AN apparatus to the UE; or when the sum of bandwidth constraint conditions is less than or equal to the subscribed bandwidth constraint condition of the user packet, performing, based on the sum of bandwidth constraint conditions, bandwidth constraint on a downlink user packet received by the AN apparatus from the UP and forwarded by the AN apparatus to the UE