Validity detection method, validity detection device and validity detection system

The invention discloses a validity detection method, a validity detection device and a validity detection system, and belongs to the field of communication. The method comprises the steps of receiving unencrypted data and a first encryption value sent by a data sending end, wherein the first encryption value is generated by the data sending end by encrypting the unencrypted data with a first preset key; encrypting the unencrypted data with a second preset key to generate a second encryption value; detecting whether the first encryption value and the second encryption value are the same; and determining that the data sending end is a valid data source if the detection result shows that the first encryption value and the second encryption value are the same. According to a method in which the IP addresses of both parties are verified, the security cannot be guaranteed as the IP address can be easily forged, and the validity of a data source can be verified only after the other party is notified if the IP address of one end is changed, which results in the increase of the running cost. By adopting the method of the invention, the problem is solved. The complexity of verification is reduced, the running cost is reduced, and the accuracy of validity detection of data sources is improved.