The invention relates to the technical field of information safety, in particular to a device and a method of data communication by storing a digital
certificate private key. The device of the data communication by storing the digital
certificate private key comprises an audio input / output module, an audio conversion module, a private
key management module, a
near field communication (NFC) module, a power supply module and a micro-controller, wherein the audio input / output module is used for being connected and communicated with mobile terminal audio and data, the audio conversion module is used for carrying out mutual conversion and decryption
processing on the audio and the data, the private
key management module is used for carrying out storage through a
certificate and a private key and carrying out data invoking and business signature during the process of identity
authentication, the certificate and the private key are applied for through
public key infrastructure (PKI) /
certificate authority (CA), the NFC module is used in data communication at short ranged through the NFC technology, the power supply module is used for supplying power through a mobile terminal, the micro-controller is used for being connected with the modules and carrying out initialization, state transition and powering up of an interface circuit uniformly. According to the device and the method of the data communication by storing the digital certificate private key, a mobile terminal audio port is adopted to carry out data communication and exchange, and the range of application of a digital certificate is enlarged. The device and the method of the data communication by storing the digital certificate private key is suitable for the identity
authentication of various application business of
mobile internet and capable of improving reliability and credibility of
network awareness.