The exchangeable key solutions and homomorphic encryption solutions were analyzed. Meanwhile, the deficiencies of these two solutions on the computational complexity were pointed out. On the basis of that, two new solutions were put forward: one was based on chaotic encryption solution, and the other was asymmetric encryption solution which introduced the incredible third party. The correctness, security and complexity of them were analyzed and verified. The comparison between the proposed solutions and the existing ones was given. The experimental results show that the new solutions can reduce the complexity of the algorithm, and greatly improve the execution efficiency of algorithm.