Mobile device for detecting route overlap and methods thereof

A route overlap detecting method of a mobile device, the method comprising:

• calculating and storing location information;
• performing homomorphic encryption on a plurality of pieces stored location information and generating movement path information of the mobile device;
• transmitting the movement path information to a server apparatus;
• based on operation result data obtained by operating based on the movement path information and comparison target path information being received from the server apparatus, decrypting the operation result data;
• and
• outputting a message notifying whether a route overlaps the comparison target path information based on a decrypted result.

A server apparatus comprising:

• a communicator;
• a memory;
• and
• a processor,
• wherein the processor is configured to, based on comparison target path information corresponding to a movement path of a patient being received through the communicator, store the comparison target path information in the memory, and
• based on movement path information subjected to homomorphic encryption being received from a mobile device through the communicator, subtract the movement path information subjected to homomorphic encryption from the comparison target information, multiply random data by the subtraction result to calculate operation result data, and transmit the operation result data to the mobile device through the communicator.

A recording medium storing a program code for performing a route overlap detecting method of a terminal apparatus, the route overlap detecting method comprising:

• calculating and storing location information of the mobile device;
• performing homomorphic encryption on a plurality of pieces stored location information and generating movement path information of the mobile device;
• transmitting the movement path information to a server apparatus;
• based on operation result data obtained by operating based on the movement path information and comparison target path information being received from the server apparatus, decrypting the operation result data;
• and
• outputting a message notifying whether a route overlaps the comparison target path information based on a decrypted result.