Abstract: This paper analyzed three kinds of business models of bank and pointed out that the modern "machine-machine" model is the trend of future bank' business, but the key technical problem is to discern the clients' identity and to ensure the safety of information in transmitting. Two kinds of security control methods, the two private keys strategy and the intelligent automatic speech recognition, were presented. To the former, it is not necessary to discern the clients' identity; and to the latter, the dynamic voice, replaced the dynamic figures, was used to discern the clients' identity compared with the traditional method. Here also presented a frame description of the strategies and algorithms for solving the hard problem.