A method of route aggregation handling for 3rd Generation Partnership Project, 3GPP, Control Plane and User Plane Separation, CUPS, architecture, comprising: allocating, by a Control Plane, CP, node, an Internet Protocol, IP, Address from an IP pool to a selected User Equipment, UE, for a Packet Data Unit, PDU, session, the IP pool being configured with IP pool blocks comprising routes for packet routing; performing, by a User Plane, UP, node, data traffic routing between an internet service provider, ISP, and the UE using routes from the IP pool; and sending, by the CP node to the UP node, as part of one of an association setup request or an association update request during one of a start or update of an association between the CP node and the UP node, one of: i) transmission routes in the IP pool to be used for the data traffic routing between the ISP and the UE, wherein the transmission routes to be used are provided by the CP node in a route aggregation information element within the one of the association setup request or the association update request sent to the UP node; or ii) transmission routes to be deleted from the IP pool for the data traffic routing between the ISP and the UE, wherein the transmission routes to be deleted are provided by the CP node in a vendor-specific Information Element, IE, within the one of the association setup request or the association update request sent to the UP node, wherein the transmission routes to be used by the UP are contained in an IP pool Aggregation field within said vendor-specific IE further comprising: sending, by the UP node to a next hop router, a Border Gateway Protocol, BGP, Update message containing the IP pool Route Aggregation field. allocating, by a Control Plane, CP, node, an Internet Protocol, IP, Address from an IP pool to a selected User Equipment, UE, for a Packet Data Unit, PDU, session, the IP pool being configured with IP pool blocks comprising routes for packet routing; performing, by a User Plane, UP, node, data traffic routing between an internet service provider, ISP, and the UE using routes from the IP pool; and sending, by the CP node to the UP node, as part of one of an association setup request or an association update request during one of a start or update of an association between the CP node and the UP node, one of: i) transmission routes in the IP pool to be used for the data traffic routing between the ISP and the UE, wherein the transmission routes to be used are provided by the CP node in a route aggregation information element within the one of the association setup request or the association update request sent to the UP node; or ii) transmission routes to be deleted from the IP pool for the data traffic routing between the ISP and the UE, wherein the transmission routes to be deleted are provided by the CP node in a vendor-specific Information Element, IE, within the one of the association setup request or the association update request sent to the UP node, i) transmission routes in the IP pool to be used for the data traffic routing between the ISP and the UE, wherein the transmission routes to be used are provided by the CP node in a route aggregation information element within the one of the association setup request or the association update request sent to the UP node; or ii) transmission routes to be deleted from the IP pool for the data traffic routing between the ISP and the UE, wherein the transmission routes to be deleted are provided by the CP node in a vendor-specific Information Element, IE, within the one of the association setup request or the association update request sent to the UP node, wherein the transmission routes to be used by the UP are contained in an IP pool Aggregation field within said vendor-specific IE further comprising: sending, by the UP node to a next hop router, a Border Gateway Protocol, BGP, Update message containing the IP pool Route Aggregation field.