A communication system in which multiple logical paths are configured in a core system of a mobile network to perform communication, characterized by comprising: a plurality of Packet Data Network, PDN, gateways (720-1, 720-2); a virtual serving gateway including a plurality of virtual user-plane serving gateways (740-1, 740-2), one per PDN gateway (720-1, 720-2), wherein an IP address is assigned to the virtual serving gateway ; a transport network between a base station and the plurality of virtual user-plane serving gateways (740-1, 740-2), the transport network comprising a plurality of switches and a control apparatus that is adapted to control the transport network : to construct, for each of the plurality of virtual user-plane serving gateways (740-1, 740-2), a different logical path in the form of a respective GTP-U tunnel in the transport network interconnecting the base station and one of the virtual user-plane serving gateways (740-1, 740-2), wherein each GTP-U tunnel is identified by a respective Tunneling Endpoint Identifier, TEID, assigned to the GTP-U tunnel; to decide on which switches of the plurality of switches the respective GTP-U tunnel will pass through; and to instruct the plurality of switches to forward packets with the same IP address as the virtual serving gateway but different TEIDs, as encapsulated by the base station, via the respective switches of the corresponding GTP-U tunnel. a plurality of Packet Data Network, PDN, gateways (720-1, 720-2); a virtual serving gateway including a plurality of virtual user-plane serving gateways (740-1, 740-2), one per PDN gateway (720-1, 720-2), wherein an IP address is assigned to the virtual serving gateway ; a transport network between a base station and the plurality of virtual user-plane serving gateways (740-1, 740-2), the transport network comprising a plurality of switches and a control apparatus that is adapted to control the transport network : to construct, for each of the plurality of virtual user-plane serving gateways (740-1, 740-2), a different logical path in the form of a respective GTP-U tunnel in the transport network interconnecting the base station and one of the virtual user-plane serving gateways (740-1, 740-2), wherein each GTP-U tunnel is identified by a respective Tunneling Endpoint Identifier, TEID, assigned to the GTP-U tunnel; to decide on which switches of the plurality of switches the respective GTP-U tunnel will pass through; and to instruct the plurality of switches to forward packets with the same IP address as the virtual serving gateway but different TEIDs, as encapsulated by the base station, via the respective switches of the corresponding GTP-U tunnel. to construct, for each of the plurality of virtual user-plane serving gateways (740-1, 740-2), a different logical path in the form of a respective GTP-U tunnel in the transport network interconnecting the base station and one of the virtual user-plane serving gateways (740-1, 740-2), wherein each GTP-U tunnel is identified by a respective Tunneling Endpoint Identifier, TEID, assigned to the GTP-U tunnel; to decide on which switches of the plurality of switches the respective GTP-U tunnel will pass through; and to instruct the plurality of switches to forward packets with the same IP address as the virtual serving gateway but different TEIDs, as encapsulated by the base station, via the respective switches of the corresponding GTP-U tunnel. <EOS>