Traffic Offload Mechanism in EPC Based on Bearer Type

The flat architecture becomes the evolution direction of the next generation Mobile Communication Network. It can also lighten the load on the core network effectively. The LIPA (Local IP Access) and SIPTO (Selected IP Traffic Offload) proposed by 3GPP are the typical technologies to implement the flat traffic offload in the user side. Current offload mechanisms for LIPA/SIPTO are either costly for both of the operators and terminals, or too complex to standardize, and the utilized grain sizes are not so appropriate for control. The study in this paper proposes a new offload policy mechanism, to support a simple, reasonable and effective LIPA/SIPTO solution, as well as solve the existing problems. It is implemented in the operator´s core network in a bearer granularity (the bearer based offload mechanism in the core network, B2OMICN). By analyzing the bearer information and marking an offload type flag, the mechanism performs offload evaluation well in the comparison.