Data forwarding method and device

A method for forwarding data, wherein the method comprises:

• receiving, by a source local base station, a Handover Indication message transmitted by a source macro base station to instruct a User Equipment (UE) to be handed over to a target base station, wherein a control plane of the UE is only connected with the source macro base station, a user plane of the UE is connected with the source local base station, and all or a part of bearers of the user plane of the UE are separated from all bearers of the control plane of the UE;
• and
• transmitting, by the source local base station, acknowledgement information of successful transmission of Packet Data Convergence Protocol (PDCP) data packets to the source macro base station, so that the source macro base station obtains and transmits to the target base station, sequence number transmission status information of uplink and downlink PDCP data packets of the UE from the PDCP data packets, for which no acknowledgement indicator of successful transmission is available from the source local base station, among PDCP data packets locally stored in the source macro base station according to the acknowledgement information of successful transmission, wherein the target base station is a macro base station providing underlying coverage in another layered network adjacent to the source macro base station, or a base station in another non-layered network.

A network-side device, comprising:

• a processor configured to obtain sequence number transmission status information of uplink and downlink Packet Data Convergence Protocol (PDCP) data packets of a source local base station currently accessed by a User Equipment (UE), wherein a control plane of the UE is only connected with the network-side device, a user plane of the UE is connected with the source local base station, and all or a part of bearers of the user plane of the UE are separated from all bearers of the control plane of the UE;
• and
• a signal transceiver configured to transmit the sequence number transmission status information to a target base station to which the UE is to be handed over, so that the target base station sets up a user plane connection with the UE according to the sequence number transmission status information, wherein the target base station is a macro base station providing underlying coverage in another layered network adjacent to the network-side device, or a base station in another non-layered network;
• wherein the processor is further configured:
• to obtain the sequence number transmission status information from a sequence number status report transmitted by the source local base station;
• or
• to obtain the sequence number transmission status information from the PDCP data packets, for which no acknowledgement indicator of successful transmission is available from the source local base station, among PDCP data packets locally stored in the network-side device.