A method in a radio communication system for assigning a short-lived Cell Radio Network Temporary Identifier, "C-RNTI", to a first user equipment performing random access to a radio network node, wherein the method comprises: registering (303, 312) the first user equipment as connected to the radio network node, wherein the short-lived C-RNTI is assigned to the first user equipment for identification thereof during a first time period; and transferring (304, 313), from the radio network node to the first user equipment, a message for synchronizing the radio network node and the first user equipment with respect to the first time period; and before the first time period has elapsed: associating, by the radio network node, a first extended C-RNTI to the first user equipment, wherein the first extended C-RNTI comprises a first set of bits and a second set of bits, and wherein number of bits of the first set is equal to number of bits of the short-lived C-RNTI; and after the first time period has elapsed: maintaining (305, 314) the first user equipment connected to the radio network node; allowing the short-lived C-RNTI to be assigned to a second user equipment, thereby enabling use of the short-lived C-RNTI for identification of the second user equipment when connected to the radio network node; and assigning downlink transmission resources to the first user equipment by utilizing the first extended C-RNTI as a means for identifying the first user equipment on a Physical Downlink Control Channel, PDCCH. registering (303, 312) the first user equipment as connected to the radio network node, wherein the short-lived C-RNTI is assigned to the first user equipment for identification thereof during a first time period; and transferring (304, 313), from the radio network node to the first user equipment, a message for synchronizing the radio network node and the first user equipment with respect to the first time period; and before the first time period has elapsed: associating, by the radio network node, a first extended C-RNTI to the first user equipment, wherein the first extended C-RNTI comprises a first set of bits and a second set of bits, and wherein number of bits of the first set is equal to number of bits of the short-lived C-RNTI; and after the first time period has elapsed: maintaining (305, 314) the first user equipment connected to the radio network node; allowing the short-lived C-RNTI to be assigned to a second user equipment, thereby enabling use of the short-lived C-RNTI for identification of the second user equipment when connected to the radio network node; and assigning downlink transmission resources to the first user equipment by utilizing the first extended C-RNTI as a means for identifying the first user equipment on a Physical Downlink Control Channel, PDCCH. associating, by the radio network node, a first extended C-RNTI to the first user equipment, wherein the first extended C-RNTI comprises a first set of bits and a second set of bits, and wherein number of bits of the first set is equal to number of bits of the short-lived C-RNTI; and after the first time period has elapsed: maintaining (305, 314) the first user equipment connected to the radio network node; allowing the short-lived C-RNTI to be assigned to a second user equipment, thereby enabling use of the short-lived C-RNTI for identification of the second user equipment when connected to the radio network node; and assigning downlink transmission resources to the first user equipment by utilizing the first extended C-RNTI as a means for identifying the first user equipment on a Physical Downlink Control Channel, PDCCH. maintaining (305, 314) the first user equipment connected to the radio network node; allowing the short-lived C-RNTI to be assigned to a second user equipment, thereby enabling use of the short-lived C-RNTI for identification of the second user equipment when connected to the radio network node; and assigning downlink transmission resources to the first user equipment by utilizing the first extended C-RNTI as a means for identifying the first user equipment on a Physical Downlink Control Channel, PDCCH.