A method for receiving a Buffer Status Report, BSR, comprising: sending, by a master Evolved Node B, MeNB, to User Equipment, UE, an allocation rule for buffer data, which is to be allocated among the MeNB and at least another small-cell eNB, SeNB, of radio bearers, the buffer data comprising buffer data in a Packet Data Convergence Protocol, PDCP layer and a Radio Link Control, RLC layer, the allocation rule comprising information about an allocation proportion for a value of a data buffer space in the PDCP layer and the allocation rule comprising values of a data buffer space of the RLC layer for the MeNB and the SeNB respectively; wherein the information about the allocation proportion comprises: the information about the allocation proportion is a proportion relationship of buffer data in the PDCP layer of specific bearers belonging to Logical Channel Groups, LCGs, among the MeNB and the at least another SeNB, wherein the specific bearers are all or a part of Data Radio Bearers, DRBs, or signalling radio bearers; and receiving, by the MeNB and the at least another SeNB, a BSR from the UE; wherein receiving, by the MeNB and the at least another SeNB, the BSR from the UE comprises: receiving, by each of the MeNB and the at least another SeNB from the UE, a BSR comprising a size of buffer data of the respective RLC layer for the respective MeNB and SeNB according to the respective value of RLC buffer data and a size of buffer data in the PDCP layer of a first radio bearer belonging to a first LCG and a size of buffer data in the PDCP layer of a second radio bearer belonging to a second LCG, the size of buffer data of the first radio bearer which data is to be sent to the MeNB and the size of buffer data of the first radio bearer which data is to be sent to the at least another SeNB being determined by the UE according to the allocation rule, and the size of buffer data of the second radio bearer which data is to be sent to the MeNB and the size of buffer data of the second radio bearer which data is to be sent to the at least another SeNB being determined by the UE according to the allocation rule. sending, by a master Evolved Node B, MeNB, to User Equipment, UE, an allocation rule for buffer data, which is to be allocated among the MeNB and at least another small-cell eNB, SeNB, of radio bearers, the buffer data comprising buffer data in a Packet Data Convergence Protocol, PDCP layer and a Radio Link Control, RLC layer, the allocation rule comprising information about an allocation proportion for a value of a data buffer space in the PDCP layer and the allocation rule comprising values of a data buffer space of the RLC layer for the MeNB and the SeNB respectively; wherein the information about the allocation proportion comprises: the information about the allocation proportion is a proportion relationship of buffer data in the PDCP layer of specific bearers belonging to Logical Channel Groups, LCGs, among the MeNB and the at least another SeNB, wherein the specific bearers are all or a part of Data Radio Bearers, DRBs, or signalling radio bearers; and receiving, by the MeNB and the at least another SeNB, a BSR from the UE; wherein receiving, by the MeNB and the at least another SeNB, the BSR from the UE comprises: receiving, by each of the MeNB and the at least another SeNB from the UE, a BSR comprising a size of buffer data of the respective RLC layer for the respective MeNB and SeNB according to the respective value of RLC buffer data and a size of buffer data in the PDCP layer of a first radio bearer belonging to a first LCG and a size of buffer data in the PDCP layer of a second radio bearer belonging to a second LCG, the size of buffer data of the first radio bearer which data is to be sent to the MeNB and the size of buffer data of the first radio bearer which data is to be sent to the at least another SeNB being determined by the UE according to the allocation rule, and the size of buffer data of the second radio bearer which data is to be sent to the MeNB and the size of buffer data of the second radio bearer which data is to be sent to the at least another SeNB being determined by the UE according to the allocation rule.