Method and system for data packet shunting transmission

The invention discloses a method for data packet shunting transmission. The method comprises steps as follows: an RLC SDU (radio link control service data unit) data flow sent by a PDCP (packet data convergence protocol) layer is converted into a first RLC PDU (RLC protocol data unit) data flow and a second RLC PDU data flow by the aid of an M-RLC (master-radio link control) layer; the first RLC PDU data flow is sent to a first MAC (medium access control) layer, the second RLC PDU data flow is sent to an S-RLC (secondary-radio link control) layer, segmentation and/or cascading treatment as well as addition/modification of PDU packet headers are performed on all RLC PDUs in the second RLC PDU data flow by the aid of the S-RLC layer, and the RLC PDUs are sent to a second MAC layer; the first RLC PDU data flow and the second RLC PDU data flow are sent to a receiving end respectively by the aid of the first MAC layer and the second MAC layer. The invention further discloses a system for data packet shunting transmission. With the adoption of the method and the system for data packet shunting transmission, the service requirement of UE (user equipment) for the high mobility can be met while the large data volume requirement of the UE can be met.