Resource sharing device, communication network, and resource sharing system and method

The invention provides a resource sharing device. The resource sharing device comprises a label adding unit and an interaction unit, wherein the label adding unit is used for adding characteristic labels to data information according to a first communication network to which any terminal belongs and a mark of any terminal when receiving the data information transmitted by any terminal from the first communication network; the interaction unit is used for transmitting the data information and the characteristic labels corresponding to the data information to a second communication network and transmitting the data information to a target mobile through the second communication network. Correspondingly, the invention further provides a resource sharing method. With the adoption of the technical scheme, passed-back resources of a plurality of operators can be shared so as to overcome the defect that a pass-back network is established by consuming huge investment is overcome; the load between the two networks is balanced and the resource utilization rate is increased.