A control device (D1, D2) is dedicated to a first or second network equipment (SR.DR.N1-N3) of a radio access network (RN) of a mobile network. A first type network equipment (N1-N3, DR) is arranged to allocate radio capacities for connections between user equipments (UE1-UE6) and a second type network equipment (SR) through an i.nu.b or lur interface, and a second type network equipment (SR) is arranged to transmit data Hows through an iub or lur interface to at least one first type network equipment according to allocated radio capacities. The device (D1, D2) comprises a processing means (PM) arranged i) to determine if a congestion has occurred on the lub and/or lur type interface(s) to which its network equipment is connected to, and if) in case of interface congestion determination, either to determine (for first type network equipment (DR, N1-N3)) new and lower allocated radio capacities for at least some chosen radio connections of the congested interface (Iub, lur) in order the sum of all the allocated radio capacities into this congested interface be lower or equal to the interface transmission capacity, or to reduce (for second type network equipment (SR)) the data transmission rate of at least some chosen radio connections of the congested interface (lub, lur) in order the sum of all the data transmission rates into the congested interface be lower or equal to the interface transmission capacity.